IMPORTANT! NOTE FROM THE EDITOR - Change of
thinking about GD
Midwifery has often been skeptical of the idea of gestational
diabetes and the idea that healthy women can suddenly become
pathological during pregnancy. This has often been true in
the past. However, I would now say that our cultural way of
eating has become so pathological that pregnant women need to be
very mindful of their blood sugar levels in order to have the best
possible outcome. For all women, regardless of the results
of the gestational diabetes screen, I recommend a full day of self
monitoring of blood sugars at 24, 28, 32 and 36 weeks to see how
their diets and lifestyle are affecting their blood sugars.
The beauty of self-testing is that it allows you to find the carb
culprits in your diet and provides an opportunity to do something
about it right away, i.e. EXERCISE!
In the past, we were mostly concerned about borderline blood
sugar issues making the baby bigger.
New research shows that high blood
sugar levels also affect the maturation of the uterus and its
ability to contract effectively. This can explain the high
levels of amniotic fluid we see, the postdates, the
postpartum hemorrhage, and the occasionally dysfunctional labor.
In addition, a woman's blood sugar levels during pregnancy affect
her own likelihood of developing Type II diabetes either
immediately after the pregnancy or later in life.
AND, in case you're not convinced yet, a woman's blood sugar
levels during pregnancy seem to increase the child's risk of
developing diabetes or obesity.
More later . . .
A diagnosis of gestational diabetes is something that you can be
grateful for because it gives you information you need in order to
help your pregnancy to continue on an even keel into the last
trimester and to prevent complications. The diagnosis simply
means that your body is very efficient about turning your food
into blood sugar and keeping it there to help your baby
grow. This was probably very helpful to your ancestors when
food was scarce. Unfortunately, with our modern processed
foods, it's way too easy to turn foods into blood sugar, and this
is where the problem comes in.
Taking care of yourself with a diagnosis of gestational diabetes
just means that you need to take extra care so that your blood
sugars don't get too high and stay too high. You do this by
eating foods with a low glycemic index (i.e. avoiding simple
sugars or refined carbohydrates) and exercising after meals to
help your body process your food in a healthy way.
When you think about it, this is what our ancestors did for
thousands of years. They didn't have access to processed
sugars and carbohydrates, and they were always "exercising" by
walking around. If you're looking for something positive
here, you can think about how this is reconnecting you with your
long-ago maternal ancestors, and you can think about how they gave
birth to a healthy baby without any interventions at all!
(Otherwise, you wouldn't be here.)
Tanvig M, Wehberg S, Vinter C, Joergensen J, Ovesen P,
Beck-Nielsen H, Jensen D, Christesen H.
BJOG. 2013 Feb;120(3):320-30. doi: 10.1111/1471-0528.12062.
Epub 2012 Nov 12.
CONCLUSION: Birth AC and weight are affected by maternal smoking
status and pregestational BMI. Pregestational BMI correlated more
to birthweight than to AC. Using data from healthy, nonsmoking
mothers with normal pregestational BMI we have provided new
reference curves for birth AC and birthweight. [Ed: This isn't
really a huge surprise, but it does support increased attention to
blood sugar issues in women with a higher BMI at the start of
pregnancy.]
How to Add Resistant Starch to Your Diet
When increasing fiber intake, go slowly and drink plenty of water to reduce GI side effects. Remember all types of fiber have health benefits so eat a variety of fiber-containing foods.
Al-Qahtani S, Heath A, Quenby S, Dawood F, Floyd R, Burdyga T,
Wray S.
Diabetologia. 2012
Feb;55(2):489-98. Epub 2011 Nov 19.
Diagnosis of insulin resistance and/or prediabetes in the general population can point to several interventions that may reduce the risk of eventually developing full-blown diabetes and/or cardiovascular disease. That is pretty important.
In pregnancy, the reason for doing an early (before 20 weeks) diabetes screen is to diagnose pre-existing diabetes. Ideally, real diabetes would be picked up before even getting pregnant, because high sugars in the embryonic stage are teratogenic (as much as a 10% rate of major congenital anomalies including heart and kidney stuff). Think about it this way - blood with elevated glucose is hyperosmolar and nutrients can't be transported properly across the cell membranes. This sets off an inflammatory response as well, and the placenta doesn't embed properly, hence the higher association with pre-eclampsia and abruption later on (in uncontrolled pre-gestational diabetics). The earlier the diagnosis is made, the earlier you can try to correct the situation.
The risk factors that would cause me to want to get an early
glucose test in pregnancy are those for diabetes in anyone -
obesity as defined by elevated BMI, history of prior glucose
intolerance, PCOS (or hx of PCOS like symptoms), prior gestational
diabetes, prior baby > 5000 gms. I am not real thrilled
with the idea of testing everyone at 28 weeks, but there are
certainly some moms who I want to test early and repeat the test
on (if first test was normal). I have also been very
surprised to find significant glucose intolerance in a couple of
extremely thin Asian women recently. [Ed: I've heard a number of
midwives observe that Asians are much more likely to be diagnosed
as gestational diabetics; is this because we're using studies on
non-Asians to establish blood sugar levels that may or may not be
relevant for Asians?]
I like to do a hemoglobin A1C with the initial labs for all my
clients to see what her glucose levels were like before pregnancy.
Studies
Suggest Ways to Improve Gestational Diabetes Outcomes
[4/15/16] - Two new studies suggest that earlier screening for
gestational diabetes and a lower diagnostic threshold for
treatment each may reduce the maternal and fetal risks associated
with the condition. . . . Both studies, she added, show that
treating and controlling GDM even with earlier screening or
broader criteria can improve outcomes. . . . Dr Sovio and
colleagues found that fetuses of mothers with obesity and/or GDM
grew more quickly between 20 and 28 weeks of gestation than the
fetuses of mothers with neither condition. . . . "In
fact, the current data indicate that any intervention aimed at
reducing the risk of [large for gestational age] in the infants of
obese women may need to be implemented before 20 [weeks of
gestational age]." . . . "In summary, women diagnosed with mild
GDM by the less stringent Carpenter-Coustan criteria and by the
stricter National Diabetes Data Group criteria both benefit from
nutritional counseling, dietary therapy, and insulin when
indicated," the authors conclude.
Easy
Steps to Diabetes Control by David Mendosa - The researchers
from New Zealand showed that taking short walks every may be more
effective at reducing the risk of type 2 diabetes than a 30-minute
walk. How short is short? Is 100 seconds short enough for you?
That’s the length of time that they used. One minute and 40
seconds.
Breaking
prolonged sitting reduces postprandial glycemia in healthy,
normal-weight adults: a randomized crossover trial.
Peddie MC, Bone JL, Rehrer NJ, Skeaff CM, Gray AR, Perry TL.
Am J Clin Nutr. 2013 Aug;98(2):358-66. doi:
10.3945/ajcn.112.051763. Epub 2013 Jun 26.
CONCLUSION: Regular activity breaks were more effective than
continuous physical activity at decreasing postprandial glycemia
and insulinemia in healthy, normal-weight adults. This trial was
registered with the Australian New Zealand Clinical Trials
registry as ACTRN12610000953033.
Hyperglycemia and Adverse Pregnancy Outcomes - Glucose levels that were increased during pregnancy but were below levels diagnostic of diabetes were significantly associated with increased risks of birth weight above the 90th percentile and C-peptide levels above the 90th percentile, as well as with other adverse pregnancy outcomes.
Metformin versus Insulin for the Treatment of Gestational Diabetes - This trial compared insulin with metformin for the treatment of gestational diabetes mellitus. These results provide support for the use of metformin as initial treatment for gestational diabetes in women who require pharmacologic therapy.
Then again, this new literature review isn't that enthusiastic about testing.
Guidelines Issued About Lack of Evidence for Screening for Gestational Diabetes CME/CE [Medscape]
"Current evidence is insufficient to assess the balance of
benefits and harms of screening for gestational diabetes mellitus,
either before or after 24 weeks' gestation," the statement
concludes. "Until there is better evidence, clinicians should
discuss screening for GDM with their patients and make
case-by-case decisions. The discussion should include information
about the uncertain benefits and harms as well as the frequency
and uncertain meaning of a positive screening test result."
Gestational
diabetes:
the consequences of not treating.
Langer O, Yogev Y, Most O, Xenakis EM.
Am J Obstet Gynecol. 2005 Apr;192(4):989-97.
OBJECTIVE: Untreated gestational diabetes mellitus carries significant risks of perinatal morbidity at all severity levels; treatment will enhance outcome. STUDY DESIGN: A matched control of 555 gravidas, gestational diabetes mellitus diagnosed after 37 weeks, were compared with 1110 subjects treated for gestational diabetes mellitus and 1110 nondiabetic subjects matched from the same delivery year for obesity, parity, ethnicity, and gestational age at delivery. The nondiabetic subjects and those not treated for gestational diabetes mellitus were matched for prenatal visits. RESULTS: A composite adverse outcome was 59% for untreated, 18% for treated, and 11% for nondiabetic subjects. A 2- to 4-fold increase in metabolic complications and macrosomia/large for gestational age was found in the untreated group with no difference between nondiabetic and treated subjects. Comparison of maternal size, parity, and disease severity revealed a 2- to 3-fold higher morbidity rate for the untreated groups, compared with the other groups. CONCLUSION: Untreated gestational diabetes mellitus carries significant risks for perinatal morbidity in all disease severity levels. Timely and effective treatment may substantially improve outcome.
[Ed: The untreated group was women who started care very late in pregnancy. One can assume that these are women who were not getting a lot of health care before pregnancy either. It occurs to me that although these women were diagnosed as having gestational diabetes, nothing was done postpartum to ascertain whether any of these women were actually overtly diabetic, a category excluded from the other study groups. Given that this study was an attempt to use a case-control study to come as close to a RCT as ethically possible, it would have seemed obvious to repeat the OGTT at postpartum intervals to separate out the results from women who were frankly diabetic, and it would have been extremely useful to know whether the slight difference in stillbirths rate was associated with undiagnosed true diabetes. The average age of the untreated GDM group is 27.6, compared to the average age of the treated GDM group, 29.1 years. This hints at an increased incidence of true diabetes in the former group. (This "oversight" is similar to the error made in the Australian study of women who weren't tested for GD; it seems obvious to me that postpartum testing would have provided some really useful additional information - maybe this is information that GD devotees don't want to know?)
The primary morbidity in this study is the baby's weight, which further affects 3 other co-morbidities: macrosomia, LGA and Ponderal Index. If a higher birth weight is a bad thing, then all women should be treated for GDM since the untreated nondiabetic group had an average birth weight that was 45 grams (1.6 ounces) higher than the treated GDM group. Or maybe GDM treatment is really making the babies smaller because it's depriving them of calories they need to grow normally?
I'm always skeptical of the hypoglycemia findings in these studies because hypoglycemia is irrelevant in a newborn who is otherwise normal, i.e. able to maintain body temperature (without the artificial cooling cause by premature bathing). Babies who were starved in utero will weigh less, and they will not have as much brown fat to metabolize to sustain the brain in the hours immediately after birth; thus they must metabolize glucose stores, possibly depleting them more quickly than the babies metabolizing their brown fat.
Interesting side note - most of the women in this study were
Hispanic, and the average gestational age at the time of birth was
39 weeks, fairly close for all study subject groups.]
Exercise
may
prevent pregnancy-related diabetes - 5/16/05 - (Reuters
Health) - Engaging in regular vigorous physical activity before
pregnancy reduces the risk of developing pregnancy-induced
diabetes (a.k.a. gestational diabetes), according to researchers.
Treating diabetes in pregnancy curbs complications - 6/13/05
NEW YORK (Reuters Health) - Treating women who develop diabetes in pregnancy (gestational diabetes) reduces the rate of serious complications without increasing the rate of cesarean delivery, new research shows.
Although the risks related to gestational diabetes are well known, it has been unclear if screening and treatment to lower maternal blood sugar levels can reduce these risks, Dr. Caroline A. Crowther and her associates comment in their report, published in The New England Journal of Medicine.
The Journal released the article early to coincide with the authors' presentation at the American Diabetes Association meeting in San Diego.
To evaluate the effects of treating gestational diabetes, Crowther, with the University of Adelaide in Australia, and her associates studied women with signs of gestational diabetes between 24 and 34 weeks into pregnancy.
By random draw, a total of 490 women were assigned to intensive treatment, including dietary advice, blood sugar monitoring, and insulin therapy, the authors note. Another 510 patients were assigned to routine care.
Serious complications among the infants -- death, shoulder impeding delivery, bone fracture, and nerve palsy -- were significantly more frequent in the routine-care group (4 percent versus 1 percent) after accounting for factors such as maternal age, race or ethnic group, and number of previous pregnancies.
A higher percentage of infants in the intervention group were admitted to the neonatal nursery (71 percent versus 61 percent), and women in the intervention group were more likely to undergo labor induction (39 percent versus 29 percent), both of which the investigators attribute to the treating physicians' knowledge of their gestational diabetes.
The rates of cesarean section were similar in the two groups.
At three months after delivery, women in the intervention group had lower rates of depression and higher scores on quality of life scales.
The report "provides some long-awaited evidence to support the use of screening and treatment for women at risk," Drs. Michael F. Greene and Caren G. Solomon, from Massachusetts General Hospital in Boston, write in an accompanying editorial.
SOURCE: The New England Journal of Medicine, June 16, 2005.
Effect
of
Treatment of Gestational Diabetes Mellitus on Pregnancy
Outcomes. [Full-text
article]
Crowther CA, Hiller JE, Moss JR, McPhee AJ, Jeffries WS, Robinson
JS.
N Engl J Med. 2005 Jun 12; [Epub ahead of print]
Background We conducted a randomized clinical trial to determine whether treatment of women with gestational diabetes mellitus reduced the risk of perinatal complications. Methods We randomly assigned women between 24 and 34 weeks' gestation who had gestational diabetes to receive dietary advice, blood glucose monitoring, and insulin therapy as needed (the intervention group) or routine care. Primary outcomes included serious perinatal complications (defined as death, shoulder dystocia, bone fracture, and nerve palsy), admission to the neonatal nursery, jaundice requiring phototherapy, induction of labor, cesarean birth, and maternal anxiety, depression, and health status. Results The rate of serious perinatal complications was significantly lower among the infants of the 490 women in the intervention group than among the infants of the 510 women in the routine-care group (1 percent vs. 4 percent; relative risk adjusted for maternal age, race or ethnic group, and parity, 0.33; 95 percent confidence interval, 0.14 to 0.75; P=0.01). However, more infants of women in the intervention group were admitted to the neonatal nursery (71 percent vs. 61 percent; adjusted relative risk, 1.13; 95 percent confidence interval, 1.03 to 1.23; P=0.01). Women in the intervention group had a higher rate of induction of labor than the women in the routine-care group (39 percent vs. 29 percent; adjusted relative risk, 1.36; 95 percent confidence interval, 1.15 to 1.62; P<0.001), although the rates of cesarean delivery were similar (31 percent and 32 percent, respectively; adjusted relative risk, 0.97; 95 percent confidence interval, 0.81 to 1.16; P=0.73). At three months post partum, data on the women's mood and quality of life, available for 573 women, revealed lower rates of depression and higher scores, consistent with improved health status, in the intervention group. Conclusions Treatment of gestational diabetes reduces serious perinatal morbidity and may also improve the woman's health-related quality of life.
What really catches my eye is that in this most recent study, they finally admit that they have not previously had good evidence to support the use of screening and treatment for women at risk. So they come up with this one study and claim that now this is the gold standard of GD studies. I don't know . . . the credibility of the medical community on this issue is very poor . . . are they just flogging a dead horse or is this real science?
I also really have to wonder at their eagerness to make the full text of this article available to the general public. They won't do this for really important articles about GBS or VBAC, but they'll do it for GD? Is this a journal article or advertising for high-intervention obstetrics?
And suddenly obstetrics is concerned about the quality of a woman's birth experience? Why isn't a woman's dissatisfaction with a bad birth experience considered a "serious perinatal outcome" when it comes to episiotomies, unnecessary cesareans and the unavailability of VBAC care?
What happens when you look at the details of this study?
Two stillbirths were unexplained intrauterine deaths at term of appropriately grown infants, and the other, at 35 weeks’ gestation, was associated with preeclampsia and intrauterine growth restriction. One infant had a lethal congenital anomaly, and one infant died after an asphyxial condition during labor without antepartum hemorrhage. There was no significant difference in the rates of shoulder dystocia between the intervention and routine-care groups (1 percent and 3 percent, respectively) (Table 2). No infant in the intervention group had a bone fracture or nerve palsy, whereas in the routine-care group, one infant had both a fractured humerus that was not related to a difficult birth and a radial-nerve palsy, one infant had Erb’s palsy related to shoulder dystocia, and one infant had Erb’s palsy alone (Table 2).Five neonatal deaths in the untreated group sounds terrible, but look at the specific reasons for death.
"Two stillbirths were unexplained intrauterine deaths at term of appropriately grown infants" - in theory, the babies would have been macrosomic if their mothers' glucose levels were unusually high.
". . . and the other, at 35 weeks’ gestation, was associated with preeclampsia and intrauterine growth restriction" - and this is related to gestational diabetes . . . how?
"One infant had a lethal congenital anomaly" - are the authors saying that GD care prevents congenital anomalies?
". . . and one infant died after an asphyxial condition during labor without antepartum hemorrhage" - it would be helpful to know more details about this case . . . was there a concealed placental abruption? Was there a cord accident? Did the mother's blood pressure drop drastically after she got an epidural? Is there any evidence that this death could have been prevented by GD care?
"There was no significant difference in the rates of shoulder dystocia between the intervention and routine-care groups (1 percent and 3 percent, respectively) (Table 2). No infant in the intervention group had a bone fracture or nerve palsy, whereas in the routine-care group, one infant had both a fractured humerus that was not related to a difficult birth and a radial-nerve palsy, one infant had Erb’s palsy related to shoulder dystocia, and one infant had Erb’s palsy alone (Table 2)." - It would be helpful to know if the case of Erb's palsy related to shoulder dystocia resolved spontaneously, as this is the only negative outcome that is plausibly related to GD care.
I notice that no retrospective testing of the bereaved mothers was mentioned. It would have seemed like really good science to do a hemoglobin A1C test on these mothers to get a good sense of their glucose levels in the preceding 3-4 months. Better yet, all women in the study should have had the same prenatal testing done so that we would know whether these bad outcomes were even occurring in women who met treatment criteria for GD.
Each of these deaths is surely tragic, but it is intellectually dishonest for the authors to imply that they would have been prevented by glucose monitoring or insulin injections. It is plausible that the 35-week death from pre-eclampsia complications might have been prevented by better overall nutrition, which is often the best side effect of GD "treatment".
If it didn't seem too outrageous to be even remotely possible, I would suggest that there were actually multiple "non intervention" groups, and the researchers simply chose the one with the worst outcomes to use as the control group.
It is mildly ironic that the hypoglycemia was lower in the "untreated" group. So much for the big concerns about rebound hypoglycemia as a consequence of untreated GD.
It is refreshing that the article considers cesarean birth to be a perinatal complication, rather than simply "an alternative to vaginal birth".
My conclusion: Women really need caring support during their
pregnancy, and if this is provided through diet counseling
associated with GD treatment, that's better than nothing.
How about trying care that's really focused on supporting the
quality of the mother's experience of pregnancy/birth/postpartum,
such as is routine in midwifery care? I'll bet that would
really reduce depression and improve health status!
Ultrasound
Measurement
of Fetal Growth Facilitates Management of Gestational Diabetes
CME
[Medscape registration is free]
Long-held prenatal beliefs challenged - [2/2/04] Screening for gestational diabetes may be another example of how resources could be better spent.
"An entire generation of obstetricians, almost two generations of obstetricians, have bought into the idea that screening for gestational diabetes is important and serves to improve pregnancy outcomes," says Ohio State OB-GYN Mark Landon.
But it's unclear whether treating mild cases, usually with diet,
is beneficial, and some research suggests it could have drawbacks,
such as an unnecessarily higher rate of C-sections. Landon leads
an ongoing, government-sponsored study to determine the
effectiveness of treating the condition.
Screening
for
gestational diabetes: a summary of the evidence for the U.S.
Preventive Services Task Force. [Medscape has an expanded
abstract, halfway down the page. Medscape registration is
free]
Brody SC, Harris R, Lohr K.
Obstet Gynecol. 2003 Feb;101(2):380-92.
These authors wrote another article - Summary
of
the Evidence - Screening for Gestational Diabetes
"Screening for GDM is contentious. The reason for this controversy
is largely a lack of high-quality research addressing the central
issues."
Medscape
offers an excellent summary
Oct., 2003 - From The UK's
National Institute for Clinical Excellence (NICE)'s CG6 Antenatal
care - routine care for the healthy pregnant woman: "The
evidence does not support routine screening for gestational
diabetes mellitus and therefore it should not be offered." (on the
bottom of page 4).
Gestational Diabetes Mellitus Diagnosed With a 2-h 75-g Oral Glucose Tolerance Test and Adverse Pregnancy Outcomes [Medscape registration is free]
"GDM based on a 2-h 75-g OGTT defined by either WHO or ADA
criteria predicts adverse pregnancy outcomes." and "Finally, our
study, being observational in nature, cannot estimate gains to be
made through diagnosis and treatment of this condition. "
In 2002, the Society of Obstetricians and Gynecologists of Canada
(SOGC) issued guidelines that it is no longer advisable to screen
every pregnant patient for gestational diabetes because the
benefits of screening have not been proven scientifically. [September
17, 2002 Volume 38 Issue 33 Medical Post.]
However, In July, 2016, the JOGC published Diabetes
in Pregnancy:
The best way of identifying and treating women with abnormal blood
glucose tests in pregnancy is not known. Raised blood glucose
levels during pregnancy is known as gestational diabetes. This
abnormality may be associated with bigger babies, more difficult
births and could be associated with higher rates of operative
delivery such as caesarean section. The review of eight studies
(1418 women) suggests that offering specific treatment for
gestational diabetes may be associated with better baby and mother
outcomes, but has not found robust evidence on the best choice of
treatment which provides the better outcomes for these women and
their babies, even if identified correctly. More research is
needed to assess long-term mother and baby outcomes.
The American Diabetes Association released new
recommendations for screening and retesting of diabetes. The
ADA now recommends that women at low risk not be screened.
(Here is their outdated
information sheet.)
Debate
over screening for gestational diabetes by Malcolm Griffiths
BMJ 1998;316:861 ( 14 March ) - Letters
From: C-upi@clari.net (UPI / Stories of modern science...from
UPI., Bill Clough (UPI))
Organization: Copyright 1997 by United Press International **
via ClariNet **
Date: Thu, 27 Nov 1997 0:51:14 PST
BOSTON, Nov. 26 (UPI) -- Toronto researchers say too many mothers-to- be are getting unnecessary blood tests for pregnancy related diabetes.
The scientists say they have developed a simple screening technique to determine who is really at risk. They estimate the technique could cut the number of such tests by one third, eliminating hundreds of thousands of tests a year.
The new screening method, an evaluation based on a woman's height, weight, age and race, would also limit false positive readings, which lead to more complicated, time consuming tests, the scientists say.
In a study in the New England Journal of Medicine, investigators from the University of Toronto used the method to screen more than 3,000 pregnant women, who were also given the standard blood test for diabetes. They found that nearly 35 percent did not need the blood tests.
Dr. C. David Naylor says the new method is "dead simple," and "picks up just as many cases as universal screening."
Naylor, a professor of medicine at the University of Toronto, also says the study found that false positives dropped about 5 percent with the new screening method.
Pregnant women are usually screened for gestational diabetes with a simple blood test, which costs around five dollars and takes an hour.
But if a women gets a false positive from the first test, she is then given an oral glucose tolerance test.
Naylor says this involves a two-day high-carbohydrate diet, fasting and giving blood four times during three hours in a blood-letting station. The woman also must drink large, sometimes nauseating, amounts of sugar water.
Naylor says, "This falls under the heading of serious nuisance for women who are already busy enough."
In a NEJM editorial, Dr. Michael F. Greene of Massachusetts General Hospital says that the study supports the American College of Obstetricians and Gynecologists and the American Diabetes Association, which call for selective screening.
But he says, "busy obstetricians are unlikely to wend their way" through a complex diagnostic screen for each pregnant woman.
(Written Mara Bovsun in New York)
Selective
Screening
for Gestational Diabetes Mellitus
Naylor CD, Sermer M, Chen E, Farine D
N Engl J Med 1997 Nov 27;337(22):1591-1596
I particularly recommend checking out the editorial. It's quite amusing, really. Well, it would be funny if it weren't so sad. The editorial acknowledges that GD testing is often unreproducible and "treatment" doesn't produce any statistically significant changes in outcome, but it still struggles to emphasize how very important it is to test as many women as possible.
Probably because of the combination of the low incidence of gestational diabetes and the extremely low incidence of perinatal mortality in developed countries, it has not been possible to demonstrate an association between gestational diabetes and perinatal mortality. More problematic has been the inability to demonstrate clearly and consistently that any intervention significantly reduces these risks. Although in some trials aggressive insulin therapy has reduced the incidence of macrosomia and operative delivery, (3) in others it has not. Despite some lingering uncertainties about the utility of making the diagnosis, (4) gestational diabetes mellitus is a real disorder, and obstetricians are obliged to recognize it.Maybe it's just my reading of it.
And I'd appreciate any insight into how the author of that editorial can claim that one of the reasons we don't see statistically significant changes in outcome because of GD "treatment" is that neonatal mortality is so low. Wouldn't a lower mortality rate just highlight any changes in outcome from GD "treatment" because the relative improvement would be greater?
A lot of this just confirms what Henci Goer says in her Emperor's New Clothes article on GD.
Gestational hypoglycemia confers favorable obstetric outcome - 6/26/05 - Determining the perinatal significance of hypoglycemia during a 100 g glucose tolerance test in pregnant women. . . . Pregnant women who experience hypoglycemia during a glucose tolerance test have a lower rate of gestational diabetes and lower neonatal birth weights than those with higher glucose levels, study results show. . . . "Based on our study, however, the patient can be reassured that such a phenomenon is not unusual, is transitory, and carries a favorable prognosis in terms of obstetric outcome," the team concludes.
Hypoglycemia
during the 100-g oral glucose tolerance test: incidence and
perinatal significance.
Weissman A, Solt I, Zloczower M, Jakobi P.
Obstet Gynecol. 2005 Jun;105(6):1424-8.
CONCLUSION: The incidence of reactive hypoglycemia during the
100-g oral glucose tolerance test in our population is 6.3%. Women
who experience hypoglycemia during the test have a significantly
lower incidence of gestational diabetes and neonatal birth
weights.
Gestational Diabetes: A Common-Sense Approach by Henci Goer
Gestational
diabetes
by Henci Goer - What is gestational diabetes? An
updated version of her classic work!
Gestational Diabetes: The Emperor Has No
Clothes by Henci Goer
Testing for and treating "gestational diabetes" does not improve
outcomes. It does not reduce miscarriage and stillbirth rates, and
it does not reduce complications typically associated with
macrosomic babies. All it does is identify women who might be at
risk for developing diabetes later in life. This has no
implications for the current pregnancy.
Gestational Diabetes: A Diagnosis Still
Looking for a Disease? by Michel Odent, M.D.
All
About Gestational Diabetes by Kmom
A Mother Summarizes Her Reasons for
Declining Glucose Screen
Treatments for gestational diabetes and impaired glucose tolerance in pregnancy (Cochrane Review)
"Reviewers' conclusions: There are insufficient data for any reliable conclusions about the effects of treatments for impaired glucose tolerance on perinatal outcome.."'
Childbirth
Connections
makes the entire chapter available.
In that BMJ discussion, Soares makes it sound as if he believes
that screening has no particular benefits for pregnancy but could
be useful as part of a general health management approach. If this
is the case, then they should be urging screening for everyone,
not just for pregnant women.
Oh, and while we are talking about evidence based practice, is
there any good evidence that glucose screening and defining women
as "gestational diabetic" has any impact on outcome?
At a conference I attended last summer, a presentation was made on GDM. Among the issues was the re-calibrating of cutoffs which is apparently in the works and moving through committees at ACOG and will be published soon. But the presenter made the point that GDM testing and identification has changed neonatal and maternal outcomes only in the ability to further identify the sub-set of the GDM population that requires insulin. This is why they want to "tighten" the cutoffs, so that more insulin-requiring GDM can be found.
The notes are at my office, but compelling information was presented about the difference in neonatal and maternal outcomes when more insulin-requiring moms were identified.
So we should be thinking about GDM this way:
Notes from a GDM presentation by Steven
Gabbe, M.D. in 1990
At 17 weeks my glucose test came back 105, and they keep saying,
"Well, let's hope that it stays low in the next test". It would be
really difficult for me to find time for the 3 hour test. Of
course if it was the best thing to do for my baby, I would, but is
it? What would the reasoning be for refusing the second test?
The reasoning for declining the second test would be the same as for declining the first test:
Testing and "treatment" doesn't improve outcomes.
Say that 100 times until you really believe it, because you'll be
made to feel that you don't love your baby if you won't let them
do everything they want to you, even if they have no evidence that
this test will help you or your baby.
When my 1st baby was born, he weighed 9 lbs 10 ozs. When
the neo-natologist came in to talk to me about his treatment, she
said that babies of mothers with GD often aspirate meconium.
Oh, I think this one takes the cake.
Yes, there is an association between higher blood sugar levels and larger babies. There is also an association between starvation and smaller babies.
Yes, there is an association between older/larger babies and meconium, because mature babies start moving their bowels in utero. Small babies also get "meconium aspiration syndrome", but they call it pneumonia if there's no meconium present, so the "association" doesn't show up on paper.
And, yes, there is an association between meconium and meconium aspiration syndrome, as in, if there's no meconium, they won't call pneumonia "meconium aspiration syndrome" - they'll just call it pneumonia. (However, research shows that removing the meconium doesn't reduce "meconium aspiration syndrome". Hmmmmm.)
Now, if they could just show that "association" has anything to do with cause and effect, then they'd have something to talk about.
I have never read anything remotely reliable about a
cause-and-effect relationship between true diabetes and meconium
aspiration syndrome (really pneumonia), and it is really really
hard to imagine how high blood sugar levels in a mom could cause
lung defects in the baby. I just did a quick search through
my files and could find absolutely no mention of meconium having
anything to do with "gestational diabetes".
It seems irresponsible to me when people say that high blood
sugar during pregnancy isn't a problem. And why would they
argue against it, anyway, when the treatment is mostly just eating
a more healthy diet and getting lots of exercise.
Yes, pathologically high levels of blood sugar can cause problems for mother and babies. The blood sugar levels used to define gestational diabetes are not pathologically high. The placenta specifically produces hormones to raise a pregnant woman's blood sugar levels. Many birth professionals throughout the world recognize this as a normal and healthy aspect of pregnancy.
Yes, a good diet and getting lots of exercise are good things for anybody, and especially for a pregnant woman. True informed consent guidelines dictate that this is exactly what I tell women. I don't lie to them about complications that might result if they don't follow my advice.
I am not arguing against eating well in pregnancy.
I am arguing about mis-representing research on the subject. I am
arguing against the erosion of self-confidence and the medical
system's assertions that women with "gestational diabetes"
couldn't grow a healthy baby without them. I am arguing
against the fallacy that testing for and treating "gestational
diabetes" is going to improve a woman's pregnancy outcome.
What makes you think that treatment for "gestational diabetes" increases your chance of VBAC? If someone has told you this, I suggest you ask for references to the studies; I don't think they exist.
Certainly, eating less is likely to decrease the size of your baby, but how is this going to increase the chance of VBAC? It's easy to think that a baby that weighs less will have a smaller head and thus be easier to birth, but this isn't the case.
What happens to a two-year-old who eats more food than they need? Do they grow taller or have a bigger head? No, they put on extra subcutaneous fat. What happens to a two-year-old who doesn't eat as much food as they need? They will probably be skinny. If they're getting way less food than they need, their growth may be stunted and they may not reach the full adult height that their genes dictated.
Restricting your food intake isn't going to result in a baby with a smaller head unless you're starving yourself. For women who are close to starvation levels, their baby may have a condition called "brain-sparing IUGR - brain-sparing IntraUterine Growth Retardation". This is where a baby isn't getting enough nutrients so sends them primarily to the head, resulting in a normal head size with a grossly reduced body size.
Notice that the word "macrosomia" means "big body", not "big head". It's no more difficult to birth a fat baby than a skinny baby, given the same size head and shoulder girdle. Fat flows and conforms to the shape of the birth canal in a way that bones cannot.
Yes, women who are "treated for gestational diabetes" may grow a baby that weighs 6-8 ounces less than it otherwise would. But the reduction is in the baby's body size and fat reserves, rather than in head size. How is this going to increase your chances for a VBAC?
It doesn't take a great stretch of the imagination to wonder how "treatment for gestational diabetes" actually increases risk of a cesarean. Women diagnosed with GD typically experience a loss of faith in their ability to grow and birth a healthy baby. Every time they measure their blood sugar or chart their food intake or inject insulin to themselves, this is a message to their body and their subconscious that there's something wrong with their body. This disempowers them at a time when feeling their power is exactly what they need in order to give birth. This loss of faith makes them more vulnerable to being pressured into making choices that aren't in their best interests, such as a pitocin induction. They may be treated as high-risk during their labor, which increases the risk of c-section.
So, I'd be curious to hear your chain of reasoning as to how treatment for GD will increase your chance of VBAC. A reference to a study would be well received.
There are many ways to improve your chances of a VBAC: it is well documented that hiring a midwife increases your chances, but you may not be able to take advantage of midwifery care if you've been diagnosed as having GD. I don't have evidence about the increased chances of a VBAC if you plan a homebirth, but I know nobody does cesareans at home.
It is well recognized that squatting opens the pelvis 20-30%. If
your care provider doesn't support squatting during pushing
(lending new meaning to the phrase "supported squat"), I would
suggest that putting energy into changing this would do a lot more
for your chances of VBAC than restricting food intake.
From - Obstetrical Ultrasound Measurements (Creighton University Medical Center):
Head size is determined largely by brain growth which is relatively independent of nutritional (maternal/placental insufficiency) growth retarding processes, and head growth is often relatively "spared" in such growth retardation. When the head growth is retarded, it is often the result of non-nutritional "symmetric growth retardation" associated with genetic, toxic, or infectious damage to the fetus.
DIET FOR THE PREVENTION OF OVERGROWTH OF THE CHILD
We have learned that it is impossible to influence the size of the child through dieting the mother. Short of actual famine there is no effect from reduction or alteration of the food. The great hunger experience in Germany during the War blockade proved this. The babies were as large and as rosy as ever -- even when the mothers were half starved. Still some physicians believe it can be done.
Joseph DeLee AM, MD, 'Obstetrics For Nurses' -- 1937
Cow's Milk Protein Linked to Diabetes
You say glycosuria is a normal finding of pregnancy?! At
what point is the level NOT normal?
Yes, I did say that glycosuria is oftentimes a normal finding of
pregnancy. We see women with 4+ glucose on dipstick urine who have
perfectly normal bloodsugars.
I have had her do random sugars (all wnl) and we did a GTT at 28
weeks which consisted of a FBS followed by Anne Frye's high sugar
breakfast and then we did 1 and 2 hour post-prandials all again
wnl.
I have no idea what Anne Frye's high sugar breakfast is. However,
normal FBS, normal postprandial glucoses, and normal glucoses
after high glucose load pretty much rule out gestational diabetes.
About
Preparing for the Glucose Tolerance Testing
I am still very curious as to why she is running such high
glucose on the dipsticks??? Any ideas??
Increased renal blood flow, increased glomerular filtration,
decreased reabsorption of glucose all result in glycosuria as a normal
pregnancy finding. She is running high glucose on dipstick simply
because she is a pregnant woman. There is nothing wrong
with this woman!!! You have checked her blood glucoses and they
are fine....therefore, her glycosuria is attributed to the normal
physiologic renal changes of pregnancy.
Why isn't it clear to everyone that this woman's kidneys are filtering the glucose through rather than attributing it to elevated blood sugar despite the normal tests?
Renal function changes remarkably in pregnancy. Glomerular
filtration rate increases nearly 50%. The capacity of the renal
tubules to reabsorb filtered glucose decreases. Because more
glucose is reaching the kidney, and less is being reabsorbed,
glycosuria is a normal finding in pregnancy.
I think one can substantiate the statement "occasional glycosuria
- trace to one plus - is normal in pregnancy", but large amounts
and on every occasion is pretty unusual.
I would have to disagree (respectfully, of course [grin]). I've had three women in the last year who've consistently spilled large amounts (+3 to +4 on our dipsticks) of sugar in their urine. One came to care late from a family doc, with normal blood glucose results in hand, saying, "Yeah, I did this last pregnancy, too". The other two I tested, and both were fine. One of my partners has had one or two this year as well, with the same results. I've got another one right now, who says the same thing....that she spilled sugar her last pregnancy.
My complaint, frankly, is the 1 hr. 50 gm. glucose challenge. I'm
almost at the point where I'd like to say, trash the damn thing.
Almost every woman that I've sent for the challenge (or screen,
whatever you call it) has come back high (>7.8 mmol/L). Then I
send them for the 3 hr OGGT, and it's fine. Strikes me I should
just save them the misery and cut to the chase.
I agree, It's a stupid test. Unless a mom has risk factors for
DIABETES (the REAL thing!) there is little point in doing one. I
believe that some women are "silent diabetics" and we might
discover the disease during her pregnancy; but I don't believe we
should be tagging normal women who have unusual gtts with the
"gestational diabetic" label.
It may be unusual, but I have seen several women over the years
like this. I have one young woman I've attended 4 births for who
has off-the-stick glucose on every visit. Her blood sugar levels
are always normal and her babies are in the 8-9 lb. range.
Glucometers have an area in which they are very accurate and at the upper and lower ends of the scale, they are not. All tests have "linearity" which is a range of values which are acceptable. Most test methods are not accurate above and below the stated linearity. For example, a glucometer might read numbers 0-30, but those values are NOT accurate when the meter's linearity states accuracy from 30-350. So , a value of 28 might actually be 12 or 38.......and the same goes for upper ranges. Often a reading over the linearity is actually higher than the machine reports.
Diet Preparation for the Three-Hour
Glucose Tolerance Test
Discussion of jellybeans as an
alternative to a cola beverage containing fifty grams of glucose
Jelly
beans
as an alternative to a fifty-gram glucose beverage for
gestational diabetes screening.
Lamar ME, Kuehl TJ, Cooney AT, Gayle LJ, Holleman S, Allen SR.
Am J Obstet Gynecol. 1999 Nov;181(5 Pt 1):1154-7.
CONCLUSIONS: Jelly beans may be used as an alternative to the
50-g glucose beverage as a sugar source for gestational diabetes
mellitus screening. The 2 sources provoke similar serum glucose
responses. Patients report fewer side effects after a jelly bean
challenge than after a 50-g glucose beverage challenge.
I agree that food is different than lab-made glucola-- so my
protocol is to do a 1 hour GCT with juice-- either apple, orange,
grape or cranberry, soda or jellybeans. If they have above
140 on the GCT we get a 3 hour and a consult with MFM. Less
false positives this way-- but we do find diabetic moms.
I send my clients to McDonald's for breakfast: Egg McMuffin is 30 g carb plus, 12 oz. OJ is 33 g carb for a total of 63 g OR Hot Cakes with 2 pats of margarine and 1 pkt of syrup is 26 g carb plus 12 oz. OJ is 33 g carb for a total of 59 g.
If they need a 3 hour challenge, they go to the lab for glucola.
I don't think it is valid to use a mixed protein/carb diet as a
substitute for a pure carbohydrate load, as in the GCT.
Protein and/or complex carbohydrates will greatly alter the
metabolism of glucose. The fact that the diet contains the
same amount of carbohydrate does not mean that it will be
metabolized in the same way as 50g glucose. Maybe just the
hotcakes with syrup would be closer to an accurate test.
Healthy
Alternatives to the Pregnancy Glucose Test [6/5/14] - This
outlines self testing at home of your normal food intake. It
also lists the contents of the Glucola, which is pretty scary!
Glucoganics Glucose Beverage - The ONLY certified ORGANIC alternative for the glucose tolerance test packaged in glass!
Juice is fructose, this is glucose which is what should be used
for the test. They are metabolized very differently so we have
stopped recommending juice.
I've started using it. They don't mind the taste, a bit honey ish.
If they purchase one its like 30$ so that's annoying. I always
felt the other options might not be as reliable, so I do like
this.
One alternative is simply to get a fasting glucose level:
Am
J
Obstet Gynecol. 1999 Nov;181(5 Pt 1):1158-61.
Alternative methods of diagnosing gestational diabetes mellitus.
Atilano LC, Lee-Parritz A, Lieberman E, Cohen AP, Barbieri RL.
CONCLUSION: An elevated glucose loading test result was
associated with but not highly predictive of gestational diabetes
mellitus. Omission of the 3-hour glucose tolerance test
measurement resulted in failure to diagnose 13% of gestational
diabetes mellitus cases. A fasting plasma glucose
concentration >/=105 mg/dL was highly predictive of an
abnormal glucose tolerance test result among patients with an
elevated glucose loading test value.
Some people are doing a one-hour or two-hour postprandial glucose
blood draw. Page
9
of this handout has instructions.
We are doing early 1 hour glucose testing on pts with a first
degree relative with a history of DM. If you are also doing this,
does it make any difference when the first degree relative
developed or was diagnosed with DM?
I think this is an interesting and useful discussion to have, because I struggle with this one quite a bit. I don't normally do the 50 gm GC (as it's called here), but will if there are risk factors (such as e.g. first order relative with type II diabetes, or persistent, heavy glycosuria). My problem is that I have, again and again, seen the 1 hour come back with a high value, and then have the woman have to move onto a 3 hour GTT, which almost always comes back with normal values. Makes me question the value of this screen a whole lot. There's not a lot of good evidence about how useful it is, yet community standards often dictate that we look better if we do it.
I have to say that I know that, a couple of times, the values on
the 1 hr have been altered because of the woman's stress levels
(one had to be poked by the lab tech 4 times, and had almost
passed out by that point...which astounded me because she has
great veins). We don't do the 1 hr ourselves, because we don't
have the glucola. Does anybody do a 2-hr pc instead, and if so, is
it "acceptable" by the powers that be?
I talk to my clients about the 50 gm glucola screen - let them know its standard of care and can help pick up a problem with glucose metabolism that they may have no other sx of. Most, however, don't eat much concentrated sweets and really don't want the glucola. There are other 50gm meals out there that I might try (just found a list of them in a conference syllabus), but I usually offer the option of a 2 hr PP glucose after a GOOD meal. I tell clients that this is not standardized and there isn't a firm desired result, but it does give us a good idea of how SHE metabolizes her own food.
Just had a primip who said she'd take the glucola - result came
back 141 (and we're supposed to do a GTT for anything >140).
She said the glucola made her feel awful for the next 24 hours and
basically refused to do a GTT involving fasting and drinking 100
mg. So we compromised with a fasting BS and a 2 hr PP - will see
if those two are normal and go from there. Again, she's another
one that doesn't eat much sugar and almost no fruit due to
allergies.
Routine GTT testing - we offer all clients @ 28 weeks a 1hour postdose GTT screening test. We explain this is the medical model standard of care, if they don't want it and they do not have risk factors that is fine with us, but I feel it is my job to offer it to them. Only if they have multiple risk factors we really push the test or if they don't want the test we have them follow a modified GDM regime, just in case. Our modified regime is really good for anyone: reduce/eliminate processed sugars, limit/dilute fruit juices, eat a complex carbo every 4-6 hours and exercise everyday.
Speaking of GDM, anyone using chromium with GDM management?
[from ob-gyn-l]
We are doing early 1 hour glucose testing on pts who have a first
degree relative with a history of DM. If you are also doing this,
does it make any difference when the first degree relative
developed or was diagnosed with DM?
I might consider it if the relative was under 60; but I think
it's pretty irrelevant if older.
we only do early 1 hr screens on women with prior hx of
gestational diabetes (just to make sure they weren't real
diabetics who just happened to be picked up during pregnancy). We
don't screen early for family hx, large babies etc.
I going to give an unpopular opinion here. I believe in Gestational diabetes (GDM), and highly recommend all women with risk factors be screened, (listed below).
I have seen too many cases over the years. Only a few were severe, but I have seen lots of mild cases. Adult onset diabetes is rapidly growing in the US. Women who get it in pregnancy have an increased chance of getting it later on in life, however it can be prevented through diet and exercise. I think screening women with risk factors is a way to positively contribute to a woman's lifetime health outlook. As a type 2 diabetic myself, with a son with type 1, I am more than aware of all the potential negative health consequences to this illness. Preventing type 2 diabetes is a long term process, we have the opportunity to intervene in a positive way with young women to help prevent a potentially very serious disease. Not to mention increased risks to both mother and baby during pregnancy.
GDM is a condition in pregnancy that is treated with nutritional changes. Often that is all it takes. Reducing sugars and simple carbohydrates, eating whole grains, frequent small meals, protein in the morning, are all healthy changes. I tell my client that not to treat GDM as a pathology but a tool for making dietary changes.
Listed below is the screening methods and values taken from the practice guidelines at Community Midwifery. From everything I have read glucometer readings are not accurate as a method of screening.
+++ Risk Factors for GDM include: +++
1) Previous GDM or abnormal blood sugars
2) Previous LGA infant (greater than 9#'s or 4000 gms) or
macrosomia or suspected LGA fetus.
3) History or presence of polyhydramnios
4) Present or anticipated maternal weight of greater than
200 lbs.
5) DM in parents or siblings
6) Previous unexplained stillbirth, anomaly, or greater than
2 previous SAB's.
7) Polyuria, Polydipsia
8) Recurrent vaginitis or UTIs
9) Recurrent glycosuria
10) Women over 35% overweight
11) Women over 30
+++ I. Screening test +++
A. Procedure for the one hour GTT is as follows:
1. Client need not be fasting & FBS need not be obtained
2. 50 gm glucola (or equivalent glucose load) is given
orally,
3. One hour later blood glucose is sent to the lab.
4. Clients with a confirmed blood glucose over 140mg/dl
require a three hour OGTT.
II. Population to be screened, and timing for testing
A. Only women with risk factors will be offered screening
for GDM at 26 to 28 weeks gestation by a one hour post 50
gram dose glucose tolerance screen.
B. Women at high risk for gestational diabetes may be
screened with a one hour post dose GTT at the first prenatal
visit. If this is initially normal, the screen will be
repeated at 26-28 weeks as in (A).
III. Follow-up for abnormal values
A. Women with abnormal values will have a three hour GTT
performed and be scheduled to be seen by MD and by nutritionist if
the three hour GTT is abnormal.
B. The following values will be used to interpret the test,
all referring to plasma glucose (not whole blood) after a 100 gram
oral glucose load.
IV. Normal values for 3 hour GTT (100 gm glucose load)
· FBS less than 105 mg/dl
· hour less than 190 mg/dl
· hour less than 165 mg/dl
· hour less than 145 mg/dl
V. Diagnosis of Gestational Diabetes
A. Two or more abnormal values of a 3 hour OGTT is
considered diagnostic for Gestational Diabetes, (Class A1).
B. A fasting Glucose greater than 120 is indicative of
a need for insulin (Class A2 or B or greater)
well, I believe in GD, too. I just think it is the diagnostic criteria are sloppy and not based on solid research -- and as a result diagnosing it seems to be almost at the whim of the care-provider.
the 50 gm carbo is a pretty good all around screen. Wouldn't hurt any of us to have one of these every five years or so. It might help if we could identify those at risk of developing type II diabetes early enough to make a difference in preventing it.
I just think the diagnosis -- and management - of "gestational diabetes" is still in its infancy.(unlike the diagnosis and treatment of diabetes mellitus). As such it is cause for confusion and still subject to errors in interpretation and implementation.. and has some possibilities of harm.
However, we both agree on the point that women with risk factors should be screened. I understand the view of screening ALL women -- even those without risk factors -- but I think of it as more of a public health issue rather than a midwife issue in my own practice. I'll watch carefully for s/s symptoms of diabetes in pregnancy - and test as needed.
In a perfect world every woman would get health screens and
health education at every stage in her life... diabetes screens,
mammograms, paps, etc. etc. Those midwives who expand into
women's health are nicely set up for that aren't they? What a
great opportunity to make a difference in a woman's life!
I think the key is to identify insulin resistance (the root of type 2 diabetes) before it develops into overt disease. We don't have any real good markers yet, except in a small subset of women (PCOS) and the gold standard for diagnosis of insulin resistance is not a good clinical tool (the insulin clamp technique). However, there is some preliminary research seeming to indicate that the ratio of the fasting glucose level to the fasting insulin level is a good surrogate marker. If the insulin is high, even though the glucose is normal, the pancreas is working overtime. A certain degree of insulin resistance is normal during pregnancy (human placental lactogen mediated) as insulin is a growth hormone (probably more significant than human growth hormone). The basic study I would like to do is to measure glucose and insulin levels with every blood draw during pregnancy for a large universe of pregnant women, and compare trends to outcomes, and see what is normal and what causes pathology. alas, no funding
amen! Double AMEN! Because THAT is at the root of the mess we've made of gestational diabetes! We know that pregnant women are insulin resistant -- and we know that this is a NORMAL STATE in pregnancy (heck, that's very old research) ... but we just really don't know "how" normal, and which levels should be used as markers to detect the abnormal.
There is not enough research and we need a hell of a lot more.
Considering that pregnant women are sort of a "captive audience",
it seems rather surprising that there is not more research into
establishing normal values for pregnant women.
Not surprising if you think about the diagnosis of GD as being one more woman who isn't eligible to receive midwifery care!
Well, call me a curmudgeon, but I don't believe enough in the research on "gestational diabetes" or believe in the validity or effectiveness (as far as preventing macrosomia) to believe in encouraging routine post-prandial testing.
The only client I can imagine "I:" think should be monitoring her glucose levels -- would be a woman with overt diabetes -- and then, she would NOT be my client, but would be referred to a specialist!
So... I can't give you any advice on which numbers to use. The fact that the numbers vary so widely in recommendation is because the research is so dang lousy. Really disgustingly lousy. And I like to quote -- or paraphrase -- The Guide to Effective Care which complains that the issue of "gestational diabetes" has been adopted with so little data that it is essentially experimentation on pregnant women and "in any other field would be considered unethical"!
Here's the deal.... research shows that restricting calories and carbohydrates will not make a statistical difference in size of the baby. Restriction of calories and carbs PLUS INSULIN "will" make a difference, but only of about 4 to 8 ounces which is not likely to be "obstetrically significant".
Any "research" you see which claims otherwise is probably based on a dozen or couple dozen moms -- read the abstracts yourself -- or on "I had this client once".
Diabetes is diabetes. A woman has it or she does not. Diagnosing gestational diabetes based on a the rather arbitrary numbers developed for GTTs is not accurate - - because the test itself is inaccurate and because there are no "normal" values set for pregnant women (who metabolise sugar differently from non-pregnant testees) There are only "abnormal" numbers based on non-pregnant people (white men) and on the guesses of various care-providers.
Diagnosing GD because the woman has a history of big babies makes no sense to me! It DOES make sense as a marker for diabetes --- because diabetic moms may tend to have larger babies -- but what about the very normal moms who are genetically programed to have big babies? they WILL have big babies -- if those babies are genetically programed to be big -- and we risk harming the mother and the baby by restricting the calories they need for their best health. They WILL have big babies anyway! Those are the facts -- and that's what the data shows.
Research does show that "normal" pregnant women need a certain level of calories and carbohydrates for optimal pregnancy health. Are we gonna deny the research proven to be true, and manipulate her diet -- depriving her of the optimum nutrition -- based on flimsy research and anecdote -- in spite of data which PROVES that diet manipulation is not effective at preventing macrosomia? [Editor's note - Macrosomia is defined as a big body relative to overall size, i.e. a "really fat" baby. Macrosomia has nothing to do with head size. "Big babies" have proportional bodies, which aren't truly macrosomic.]
A diabetic woman needs careful monitoring -- including blood-checks after every meal -- because her bloodsugars will swing wildly and jump HIGH HIGH HIGH - -- probably well into the two hundreds. But the woman called "gestatational diabetic" doesn't swing outside of the normal swing -- she has NORMAL bloodsugars for a pregnant woman -- yet the numbers are arbitrarily lowered BEYOND the normals (even normals for non-pregnancy) -- in order to "control" a nonexistent problem!
I'm sorry to grumble, whine, and complain like a petulant child. Just call me the "GD Curmudgeon".
I test my clients for DIABETES by running a random venous blood sugar when I do their labs... or if they are high risk or symptomatic I send them for a venous postprandial. IF those results are abnormal, then we deal with it -- by consultation and referral -- because she has diabetes.
If she doesn't have diabetes, then she doesn't have diabetes. And
that is the end of tests as far as I'm concerned -- unless
some overt signs/symptoms appear or there is some clinical reason
for further testing. .
So, I'm a bit confused at all the varying values available for pregnant women in regards to blood glucose. I have a client who feels she has blood sugar issues (last baby was 10#2), and after careful discussion, has opted to go with using a glucometer to check her values fasting and two hour postprandial. While I feel that she could easily birth another large baby, we do have concerns about wildly fluctuating blood sugar levels (if this is the case for her) and the effect it has on baby.
My question is this: I have about three different sets of values
that are supposedly for pregnant women - from the ADA to the WHO.
In addition, when I consulted Anne Frye's Diagnostic text, there
are two that make sense to me, but they vary greatly in values.
Some of the confusion could be because the blood sugar values/number differ by about 15% between glucometer (capillary glucose) and the testing they do when they draw blood from the arm and analyze it in the lab. Also, some places measure it in mmols, which is different than the mg/dl that I am more used to.
When I have a lady test her sugar with a glucometer, I use the same values they would use if they actually were GDM and monitoring their blood sugar. There is still some variance in the recommended values, but it's not huge. The fasting value for that is less than 95-105 (depending on whose standard you use; ACOG says 100); 1 hour after a meal should be less than 140, and 2 hours should be less than 120-130. Most glucometers are not especially reliable (see article in a recent Consumer Reports), so I have them check one of each of those values for 2 days, and figure if they all come out ok, the odds are pretty good that their sugars run WNL.
The folks that make the Hemocue for hgb measurements also make a
similar machine for measuring glucose which has FDA approval as
being as accurate as laboratory measurements. The catch is
that the little plastic cuvettes, that you get the blood in,
outdate rapidly, I think within a month of the time the container
of 25 is opened, and for most of us, our volume isn't great enough
to use that many, and they are expensive. They are supposed
to be working on another machine and packaging with fewer cuvettes
for the lower volume user, but it has not yet passed FDA approval.
[from ob-gyn-l]
Was one of the values on the GTT abnormal??? Langer has shown
that people with one abn value on the 3 hr GTT who are called
normal and not treated, have a higher incidence of fetal
macrosomia than do Gestational diabetics who are treated. He
recommends starting these people on a diabetic diet. As far as I
know, nobody else agrees with him.
Even according to ACOG or ADA there should be 2 values off
on the 3 hour GTT. in order to Dx GDM anyway. The rise of the
SECOND IS NO WAY AN INDICATION OF GDM..
In our practice we take care of many international students and faculty. We've been observing an interesting trend among our Japanese women. Surprisingly large numbers of these healthy, thin, young women with outstanding low-sugar/low-fat diets have abnormal glucose screening and then have a single elevated value on their 3 hour GTTs. The babies are normal sized. Frequently maternal weight gain in pregnancy is low by our standards, despite our exhortations for the women to eat more.
Is glucose screening based on American and/or European standards?
Is there a different standard for Asian (specifically Japanese)
women? Has anyone shown an innate difference in glucose metabolism
between these groups or might the very different diet cause a
difference in glucose metabolism?
The standards that I am aware of were established on the East
coast by O'Sullivan in Boston. I think Langer in San Antonio has
his own based on his mainly Hispanic population.
Are you giving your patient a 3 day carbohydrate load preparatory
to their GTT ?? If you don't, you will have an increased number of
false positives. Especially in patients who are on the type of
diet you describe.
Yes, we give a handout with the 3 day carbohydrate load and
instruct all women with abnormal glucose screening to follow that
diet prior to their GTT. I'm not sure the women in question
actually adhere to the diet, though. Their eyes kind of glaze over
when they read it and they clearly think that we're asking them to
add an enormous quantity of food -- more than many of them believe
they can eat.
There is no such thing as GD. When we are looking for sugar we
are looking for the women who have overt diabetes. They say there
is no sense in doing urinalysis for sugar. Are they going to
change what they check for in their clinics? NO!! Are they going
to have us stop checking for sugar?? NO!!!
But I particularly like the following line: "As no benefit has
yet been established for glucose screening during pregnancy, the
method used for this screening is irrelevant" GECPC pg 59)( and I
always feel a bit like giggling, because it's really a cute way of
saying it)
The research on this topic has shown no different outcomes, regardless of treatment. Also, GD is poorly defined, as it is normal for Blood sugar values to rise during pregnancy, so a woman may test ok in early preg, and have high values later, be diagnosed with GD, even though she has had a normal rise in BS.!!!
We have decided no routine testing, (it just makes the labs rich, and doesn't help our clients at all). We would drop urine testing for glucose except its a community standard, so that's a hard one.
If mum spills sugar there, we do a fasting ac and 2 hour pc
sugar, and consult. Haven't decided if there is any other time we
would test. Probably previous GD, more for our protection than
anything else.
This is my protocol for testing for diabetes.
No risk factors- no testing. Risk factors would include previous
GDM, sister or mother with GDM, glucose and/or ketones in urine
sample.
If a test is indicated I do a 1 and 2 hour PP in my office. I
have the client eat a "normal" meal (including a protein source, a
vegetable, a fruit and a complex carbo) an hour before her
appointment. I stick her finger as soon as her appointment starts
and an hour later. If these results are within normal range
(<140) I do nothing more unless the mother wants more testing,
if the results are borderline (140-160) I do another 1 and 2 hour
PP test in my office at her next appointment, if the results are
under 160 I discuss having a 2 hour glucose challenge done or I
will teach her how to do her own checks at home for a few weeks
with instructions to call me if any of her results go over 160. If
the results of the 1and 2 hour PP are high (>160) I suggest she
have a 2 hour glucose test at the lab. If this test comes in high,
I have her make an appointment with my back-up doctor. The few
times this had happened he has retested them and advised them to
"eat better" and to call him if a problem comes up......so far
none of my clients have needed insulin to control her high blood
glucose levels.
Some of the hospitals in our city have diabetes classes that
teach people how to do their own tests and how to eat properly. If
my client can keep her levels normal and no other signs of
problems arise, we continue with the home birth plans. If she is
unable or unwilling to get this under control, I will transfer her
care to a doctor. Period.
I would not consider mother or sister of GDM a risk factor, since I think the vast overdiagnosis makes it worthless[Grin] . I would of course consider DM a risk factor if in close family -- or appearing under age 60.
I would probably not test for only one spill of glucose either -- unless it was accompanied by ketones (then I want a full test!). Repeated glucose in the mom who is not gaining - - test! Glucose and ketones-- test today! Mom who is not gaining in spite of good diet -- or who has repeated ketones -- test! Any mom with symptoms of diabetes (thirst, frequent urination, hunger, fatigue, poor weight gain or weight loss) -- TEST [Ed: NOTE - Ketones are relevant to diabetes only for Type I diabetes where there is absolutely no insulin available in the blood stream.]
I'm more concerned about hidden DIABETES in pregnancy than in simple "glucose intolerance of pregnancy" which is what our American definition of GD is all about anyway....
If I'm getting a blood sample anyway, I will run a random glucose on it (if mom has enough money for it[Grin]). It might tell you something -- if mom really has diabetes; it probably WILL tell you something....
If I'm worried about a mom, then I like the two hour
postprandial, best!
I have had several women in the past who have had huge amounts of
glucose in their urine (as in off the pee strip chart), but every
glucose test comes back normal (or even low sometimes). These
women have had super fast labors (the word precipitous works!),
big babies and no problems at all! Anyone else see this?
yeah..... I guess by definition they might have GD, but I don't
care (about the definition[Grin]). The only risk associated with
low renal threshold/ glucose intolerance/GD is a big baby..
nothing else... Big baby/no problem -- I can live with that,
nicely!
One of my clients always has +glucose. Is there something in her
diet that could be causing it even if she's not eating any sugars?
I've heard vitamin C can cause false +, but she's not taking any.
Any ideas?
If you test her ascorbic acid and it comes out high, it could be
a false positive from vitamin C, or possibly some kind of juice
she's drinking.
Speaking from experience, some of us just have kidneys that
filter sugar back into the blood less efficiently during
pregnancy. In both of my pregnancies, I had amazingly colorful
urine dipsticks - the glucose could go out of sight after a bowl
of cornflakes and milk. But my blood glucose was always okay, and
I have 8 pound kids. I guess I wouldn't worry about it. I didn't
even bother changing my diet, nor would I advise clients to unless
the blood glucose was also high or their diet was bad anyway.
I have a 39 yo G 2 P1 now at 36 wks who has been spilling glucose in her urine since 31 wks. Her 1 hr/50 gm glucola was 108. She tends towards hypoglycemia. She's been working on her diet- eliminating all refined carbos, eating 125 gms protein a day, and small frequent meals- but still gets between trace and +2 glucose on her urine dip every time.
The only significant med hx is that she's on a small dose of
Synthroid, .112 mg a day. She has been thyroid tested twice this
pregnancy and levels were all normal.
Just suggestions --
1: perhaps a three hour test??? (I hear rumors that sometimes a true diabetic can pass the one hour test, and if we are still suspicious then we should go for a three hour will show what's going on).
2: try cutting down on the protein to perhaps 80 (certainly adequate!) - - for a week and see what happens. She may be consuming far more calories than she needs. And does "eliminating refined carbohydrates" mean that she is still using honey, syrups, corn sugars etc? ASK ABOUT JUICE OR SOFT DRINKS -- fruit juices contain a LOT of sugar!
3: Postprandials? maybe running a few be more valuable than GTTs.
4: Evaluation by ophthalmologist for "sparkles"??
5: perhaps the Synthroid is the culprit. Why is she taking it? (was there a distinct need?)
Some women just spill glucose -- no problem for them. It's
important to rule out other conditions though before we conclude
that she is "just one of those women". I usually don't worry much
about women who spill a trace or +1 from time to time -- but this
woman who seems to do it everytime up to +2 would concern me some.
I had heard somewhere that women who work too hard can have a
problem with their kidneys being overtaxed and thus not able to
filter all of the sugar out of their urine.
I only test moms with risk factors, and then we start with a one hour challenge. We do a 3 hour only if necessary.
Chromium works great for borderlines.
We offer 1 hour, nonfasting 50 gram screens to all women. We do not do FBS, with the rationale that with gestational diabetes, FBS would not be elevated anyway.I know this is controversial. I think our midwives have made significant inroads in the past years in rx of GD. In the past, most of the women with abnormal 3hour GTTs were referred to an endocrinologist, and most were put on insulin. With greater emphasis on evidence based practice and the GECPC book, the midwives have become more assertive, rarely refer to endocrinologist for GD, put women on ADA diet and things are just fine.
I think the issue is maternal weight, anyway. i.e. heavier women
are far more likely to have macrosomic infants and heavier women
are more likely to have abnormal 3hour GTTs.
[from ob-gyn-l]
I work in a not for profit HMO situation as a CNM, we have a
group of physicians who are very involved in evidenced based
medicine (none of whom do OB) and are looking at many of the
"standard of care" and "routines" that are done in our setting and
have recently looked at screening for GDM (gestational diabetes
mellitus) and have come to the conclusion that routine screening
is not beneficial or cost effective, that no reliable evidence
exists that GDM screening prevents macrosomia, and that no
randomized trials of screening have been published. They did
mention an article by Santini in the Surg Gynecol Obstet
1990;170:427-436 that determined that "the process of screening
not only failed to decrease the rate of large infants, but also
failed to improve otherwise pregnancy outcomes and was associated
with more intensive surveillance during pregnancy and a
significantly higher rate of primary cesarean delivery." What
thoughts do any of you have on this subject?
I have not reviewed the literature on this topic for several years. The following is my opinion.
I believe some years ago a study showed that the majority of women who develop GDM do not have risk factors (family history, prior pregnancy with large baby, etc.) suggesting that they are at risk for GDM. Thus, in order to identify GDM you must screen for it. Using the 3 hour GTT is not cost effective and puts patients through an unpleasant testing procedure.
The 50 g. glucose screen was "invented" as a screening test to determine who should be subjected to the 3 hour GTT. A normal screen test implies that the 3 hour GTT will be normal and that the patient is at extremely low risk for GDM. An abnormal (elevated) 50 g. screening test means that the patient may have an abnormal GTT and is at increased risk for GDM. Thus, further testing is indicated to exclude GDM.
I see the glucose screening test in the same light as the MS-AFP. They indicate if further testing is indicated or not indicated.
You can not relate the screening test to the development of a macrosomic baby nor any other problem associated with GDM, but only to the probability that a pregnant lady will have or not have an abnormal GTT.
Whether or not a pregnancy with an abnormal GTT will have
problems is another story.
Gestational
Diabetes: Please Don’t Drink the "Glucola" Without Reading the
Label - this is a helpful introduction and focuses on the
potentially toxic ingredients in some of the Glucola drinks. "at
least one of the glucose test drinks EasyDex, by Aero Med (note
that ingredient lists from the test companies are notoriously hard
to find online!) contains something called BVO, or brominated
vegetable oil. . . . the FDA removed BVO from its ‘Generally
Recognized as Safe’ list of food ingredients.” . . . it was and
remains banned from European and Japanese soft drinks. BVO is
patented in the U.S. and overseas as a flame retardant." [NOTE - A
Glucola brand that doesn’t contain artificial colors and is
BVO-free can be obtained from Azer Scientific.]
And this is a "routine" test!!
One of my clients had a two-day migraine from the Glucola.
Many midwives consider home glucose monitoring to be more useful
than the gestational diabetes screen.
David Mendosa has some good information about When to Test — And
Why: "The exception, according to the ADA, is women who have
diabetes and are pregnant. They could benefit more from testing
one hour after eating." This is for women who are not using
insulin.
He also has a nice article about the Dawn Phenomenon - That’s when fasting blood glucose readings in the morning are higher than the previous bedtime. Some women will have an elevated "fasting" glucose if they wait too long. The liver can start to secrete glucose as adrenaline rises in the morning.
Most useful relevant insurance codes from the HCPCS Level II Code
Set:
E2101 - Bld glucose monitor w lance - BLOOD GLUCOSE MONITOR WITH
INTEGRATED LANCING/BLOOD SAMPLE E2101
E0607 - Blood glucose monitor home - HOME BLOOD GLUCOSE MONITOR
(Glucose Meter)
A4253 - Blood glucose/reagent strips (50) - BLOOD GLUCOSE TEST OR
REAGENT STRIPS FOR HOME BLOOD GLUCOSE MONITOR, PER 50 STRIPS
(Glucose Test Strips)
A4256 - Calibrator solution/chips - NORMAL, LOW AND HIGH
CALIBRATOR SOLUTION / CHIPS (Control Solution)
A4258 - Lancet device each - SPRING-POWERED DEVICE FOR LANCET, EACH (Lancet Device)
A4259 - Lancets per box - LANCETS, PER BOX OF 100 (Lancets)
Relevant diagnoses:
V12.21 - Personal history of gestational diabetes (for inter-pregnancy monitoring if no other suspicions)
The
Diabetes Technology Society has a review of the accuracy of
different glucometers.
Investigation
of the Accuracy of 18 Marketed Blood Glucose Monitors
David C. Klonoff1⇑, Joan Lee Parkes2, Boris P. Kovatchev3, David
Kerr4, Wendy C. Bevier4, Ronald L. Brazg5, Mark Christiansen6,
Timothy S. Bailey7, James H. Nichols8 and Michael A. Kohn9
Diabetes Care 2018 Aug; 41(8): 1681-1688.
Gentle Testing for Diabetes - Genteel offers a new lancing
device that finally lets people with diabetes check blood
sugar levels without pain. David
Mendosa tested it and says it works. Personally, I find the
AccuChek lancets work fine for me. But someone who is
needlephobic might appreciate this extra level of comfort!
See also: Newborn Hypoglycemia
It is important that you ask your care provider how the baby will
be treated differently because of a diagnoses of gestational
diabetes in the mother. Will the baby routinely be taken to
the nursery? Will the baby's heel be stuck with a lancet to
collect blood to check glucose levels after the birth? How
often will this be done? If the baby's blood sugar is low,
will the nurses emphasize breastfeeding as the best treatment, or
will they recommend glucose water instead? If glucose water
is given to the baby, can it be given in a sippy cup or with an
SNS system so that the baby does not have to suck on a bottle and
be vulnerable to nipple confusion when breastfeeding?
"The findings suggest that the nervous system of newborns of
insulin-treated diabetic mothers is less mature than that of
babies born to healthy mothers, the researchers say. Diet-managed
diabetes is a milder condition than insulin-managed diabetes and,
therefore, the impact on sucking behavior is probably smaller,
they add."
Whether breastfeeding affects the future health of offspring of women with GDM is uncertain based on limited and conflicting findings from studies of Native Americans or women with diabetes during pregnancy. Furthermore, no studies that examined the relation of breastfeeding to development of obesity and diabetes in the offspring of women with GDM have controlled for the intrauterine metabolic environment.
Lactation may also confer health benefits to women with a history of GDM. Lactation improves glucose tolerance in the early postpartum period, but it is unclear whether future risk of type 2 diabetes is reduced.
A1C
Testing Often Fails to Spot Postpartum Diabetes [Medscape,
7/12] - Hemoglobin A1C isn't reliable for assessing postpartum
women who've had gestational diabetes mellitus (GDM), Spanish
researchers say. This is true whether it's used alone or with a
fasting glucose test, they say in a June 11 online paper in
Diabetes Care.
Triad
of Factors Ups Risk for Type 2 Diabetes [3/27/15] - Among
women who had gestational diabetes, those who had a body mass
index of 30 kg/m2 or higher before they became pregnant and then
gained 5 kg or more after giving birth were 43 times more
likely to develop type 2 diabetes than women who had a BMI of less
than 25 kg/m2 prior to pregnancy and who gained less than 5 kg in
the years that followed.
Fasting
glucose in the post-natal period
Richard IG Holt, Matthew AG Coleman2
"It seems anomalous to insist on an OGTT in the postnatal period
at a time which is probably the most inconvenient for the woman"
Obstet Gynecol. 2009 Jun;113(6):1419-21.
Establishing the diagnosis of gestational diabetes mellitus
offers an opportunity not only to improve pregnancy outcome, but
also to decrease risk factors associated with the subsequent
development of type 2 diabetes. The American College of
Obstetricians and Gynecologists' Committee on Obstetric Practice
recommends that all women with gestational diabetes mellitus be
screened at 6-12 weeks postpartum and managed appropriately.
I have a friend who took cinnamon to lower her blood sugar levels
- she was actually on insulin for her gestational diabetes but was
unhappy to have to keep upping the dose. She found that
cinnamon measurably reduced her blood sugars but not to unsafe low
levels. There is some actual objective research on cinnamon.
1/4 tsp 2 to 3 times daily - in food if possible (like on
oatmeal) . Just plain old cinnamon powder.
Do
Diet Drinks Mess Up Metabolisms? - A multi-ethnic ,
which included some 5,000 men and women, found that diet soda
consumption was linked to a significantly increased risk of both
type-2 diabetes and metabolic syndrome. [Although they
weren't specifically looking at gestational diabetes, there is an
obvious correlation with other insulin disorders.]
Taking apple cider vinegar is also supposed to help lower blood
sugars. It's worth trying anyway.
Higher magnesium intake tended to associate with lower follow-up fasting glucose and IR, but not fasting insulin, postload values, or insulin sensitivity.
Any pregnant woman will benefit from the recommendations given to women who test positive for "gestational diabetes": good nutrition and regular, moderate exercise. Here are some nutrition recommendations.
My labor coach client, diagnosed with GD, told me that her
nutritionist recommended she have no more than 1 oz/hr of Gatorade
during labor.
Has anyone been giving B6 100mg with meals to lower blood
sugar? I have used this experimentally on patients with type
2 DM and have found a blood glucose drop of 25 from their previous
averages. {The original research for the use of B6 was for
use in GDM and Glucose intolerance in pregnant women}