Glucose Tolerance test


(This is an excerpt from an upcoming book: Haas, AV; Healthy Babies! Healthy Moms! A Practical Guide to Preventing Problems during Pregnancy, Labor, and Birth , 2016)

“This is a blood test done around the 24th week of pregnancy to determine if the woman has glucose intolerance. A fasting woman is given a glucose preparation to drink, and then her blood sugar levels are tested at various times.  One of the major problems with glucose tolerance testing is that it does not necessarily tell us if a woman has gestational diabetes. What it can tell us is if her body does not handle excess glucose well (Glucose intolerance) . It can predict if a woman will be at risk for type 2 diabetes now and later in life. It may tell us that her diet needs improvement (see chapter 2). But determining if she is actually gestationally diabetic can only be determined by checking her urine for sugar, and doing more extensive testing.

The problem with the standard 1 hour GTT testing is that it can place a woman in the high risk category, when all she really needs is a change in her diet.  It is also expensive to do all this testing, but the attitude is that at least now they will get nutritional counseling. Apparently nutritional counseling is the only actual benefit here. Being labeled high risk then limits a woman’s options for the birth of her baby.  Obstetricians tend to have a cavalier attitude about the label of gestationally diabetic.  They say “oh, we can always induce you or do a cesarean”, without thinking about the additional risks of induction and surgery for both mom and baby.

Why not start with the nutritional counseling, monitor her urine, and dispense with the 1 hr. blood test?  If necessary women can test their blood sugar before and after meals, to judge its stability. As I write, the NIH is holding a conference on this subject, and the overwhelming conclusion seems to be that testing is expensive, and will change the way these women are treated, which will increase the cesarean rate.  Increasing the cesarean rate will increase infant and maternal morbidity and mortality.  In conclusion, this type of testing has not yet proven to improve outcomes, the hallmark of evidenced based medicine. What has been determined to improve outcomes is nutritional counseling.

So what should a woman do? To start with make sure your diet is rock solid. (see chapter 2). The decision to be tested is up to you, not your careprovider.  Woman whose families have a history of diabetes may choose to be tested, but if so you might want to go directly to the 2 or 3 hour test rather than the 1 hour, as they are more accurate.  In the days before you are tested make sure you eat a higher protein, complex carbohydrate diet, and avoid simple carbohydrates, such as sugar and things made from white flour.  (see page ? in chapter 3). If a woman is spilling sugar in her urine it is a sign her diet needs serious improvement, and her blood sugars many need to be tested regularly. But start with prevention – follow the Brewer pregnancy diet.”

Dekker, R. L. , Diagnosing Gestational Diabetes: The NIH Consensus Conference Day 1; 2013

Dekker, R. L. , Gestational Diabetes and the Glucola Test, 2012; 

Goer, Henci, Obstetric Myths vs. Research Realities;

From an upcoming book:

Haas, AV; Healthy Babies! Healthy Moms! A Practical Guide to Preventing Problems during Pregnancy, Labor, and Birth , 2016.

Copyright: A. V. Haas, 2016