Myth Busters: Gestational Diabetes is Indeed Real Diabetes

If you have had Gestational Diabetes you may be confused about whether this means you have "real diabetes." If your family doctor is like most you may have been told not to worry about it. Many doctors treat GD if it were nothing more than a complication of pregnancy which goes away when the pregnancy is over.

So while today's obstetricians are aggressive about helping their patients control their blood sugars through the pregnancy, as soon as the baby is delivered, they hand women with GD back to their primary care doctors whose attitude towards blood sugar control is far more relaxed, giving the woman with GD the message that their diabetes is "over."

Post-pregnancy screening, if it occurs at all may be nothing more than administering a single A1c test or, perhaps, a fasting glucose test. If these come back "Normal"--i.e. under 7% for the A1c and under 125 mg/dl (7.0 mmol/L) for the fasting glucose--the doctor will consider the case closed.

Unfortunately, it isn't closed, and the fact that you developed GD should be treated as a big red flashing warning. A new study published in the Journal of Clinical Endocrinology and Metabolism looked at the genetic make up of a group of women who had had Gestational Diabetes and compared it with a group of women who did not. They concluded "The prevalence in a prior GDM [gestational diabetes mellitus] group of several previously proven type 2 diabetes risk alleles equals the findings from association studies on type 2 diabetes. This supports the hypothesis that GDM and type 2 diabetes are two of the same entity." [emphasis mine]

This study found that the group of women who had experienced GD had a frequency of 11 different genes linked to diabetes that was very similar to that found in groups of people who have been diagnosed with Type 2 diabetes.

Common type 2 diabetes risk gene variants associate with gestational diabetes.
Jeannet Lauenborg et al. Journal of Clinical Endocrinology & Metabolism, doi:10.1210/jc.2008-1336

The only reason that your PCP doesn't think you have diabetes, is that he is using much laxer standards to diagnose than your gynecologist did.

We know that women tend to develop diabetes in a pattern where the post-meal control deteriorates many years before fasting control goes away. This is probably one reason why obstetricians screen for GD with the glucose tolerance test, NOT the fasting glucose test. But most PCPs still screen women for diabetes using only the fasting glucose test. Those who don't often rely on A1c test, a test which even the ultra-conservative ADA says should not be used for diagnosing diabetes.

Your blood sugars may be going into the diabetic range after meals but if your fasting blood sugar is only in the "impaired" range, your A1c may be somewhere between 5.9% and 6.3%. That is a value too many PCPs consider to be normal, though, in fact, it is linked by a lot of research with a much higher risk of heart disease. And even worse, blood sugars that go high after each meal make you more insulin resistant and more insulin resistance causes even higher blood sugars. They also may poison the rest of your remaining beta cells, via what is known as "glucose toxicity."

If you are a woman in the early stages of diabetes, the only test that can accurately tell you if you are diabetic is one that looks at your blood sugars after you eat a high carb meal or drink a glucose solution. The Glucose Tolerance Test is a good test. Or you can test yourself at home using the meal test described on this page: Am I Diabetic.

If you see a result over 200 mg/dl (11.1 mmol/L) after a meal two or three times make sure you have washed your hands before testing so you aren't getting sugar from your fingers on the test strip. If the reading is real, you should assume you have diabetes and get back to controlling your blood sugar the way you did when you were pregnant. The ADA's published criteria for diagnosing diabetes include two random glucose tests over 200 mg/dl (11.1 mmol/L) though many family doctors are ignorant of this fact.

Obstetricians train their patients to shoot for much lower blood sugars than do PCPs and most endocrinologists. This is because they have learned that normal blood sugars results in normal pregnancies. Unfortunately, family doctors have not gotten the message that diabetic complications can be prevented by maintaining normal blood sugars no matter what the diagnosis, so they are much less aggressive in helping people get their blood sugar back to the normal range.

Another major issue that many doctors ignore is the question of when, during your pregnancy, you developed gestational diabetes. Typically this happens towards the end of the pregnancy as women get larger and more insulin resistant.

But some of us, like, say, me, became diabetic much earlier in our pregnancy, and when this happens it may point to something different from insulin resistance being at fault. Early GD may be caused by insulin deficiency.

If you have a condition that causes beta cell dysfunction, as opposed to insulin resistance, pregnancy may unmask it. These conditions occur in in young, thin people who doctors don't think of as being at risk for diabetes, so doctors often don't notice these forms of diabetes until they have had years to ravage your body and finally cause serious symptoms. Despite my having had two diabetic pregnancies where I became diabetic very early in the pregnancy, it was more than a decade until my doctors finally thought of giving me a diabetes test that wasn't a fasting plasma glucose test.

Two forms of non-Type 2 diabetes which can cause Gestational Diabetes that arises early in the pregnancy are LADA, which is a slow-onset form of autoimmune diabetes which seems to becoming much more common over the past decade, and MODY, which is the term used to refer to a group of unrelated genetic forms of diabetes which have in common only that they are passed in dominant genes and that they limit the body's ability to control blood sugar.

You can read about LADA here: http://www.phlaunt.com/diabetes/18382053.php and about MODY here: http://www.phlaunt.com.diabetes/14047009.php.

MODY is much rarer than LADA, so if you have had GD when you were thin especially if it came on early in the pregnancy, and if you also have a family history of other autoimmune diseases, that would be the first diagnoses to have checked out.

In any case, the important thing is not what caused your gestational diabetes, so much as making sure that after you have your baby and your blood sugar seems to improve you do what it takes to keep it under control.

With that in mind, here is what I suggest you do. It is what I wish I had done after my GD pregnancies:

1. Every three months test your blood sugar after eating a high carb meal to see how your blood sugar is doing. If you see blood sugars that are over 140 mg/dl two hours after eating, test more often and work on getting your blood sugar down.

You should also put some effort into finding a doctor who will work with you to prevent your pre-diabetes from turning back into full-fledged diabetes.

There are a lot more things you can do at this "pre-diabetic" stage than there are once you've let high blood sugars kill off your beta cells. If your doctor does not take pre-diabetes seriously, find a younger, better trained doctor who will.

2. Go Easy on the Carbs!. Cut down as much as possible on the carbohydrates you eat. Don't drink high carbohydrate fruit juices, spritzers, or sodas, or eat side portions of starchy foods that will raise your blood sugar. You don't have to be obsessional about it, but before you eat something with carbs in it, stop and think: Is this carb really necessary? Some are. But most are not worth the spike they will cause in your blood sugar.

3. Start walking more and sitting less. If you are insulin resistant, exercise may help lower your insulin resistance. Walking is a lot less likely to cause injuries that put you out of commission for long periods of time than are trendier but more injury-provoking athletic pursuits. I learned this the VERY hard way, as I was too aggressive with exercise in my younger years and ended up with serious non-reparable orthopedic problems that now limit my ability to exercise. More walking and less weights and hours on the stair climber and rowing machine would have been smarter!