Missing the Mark in Gestational Diabetes?

Gestational diabetes (GDM) is one of the most common complications of pregnancy. And it can be serious. As obesity rates are growing, so too is GDM’s prevalence. But new research suggests that we’re missing the mark with the first-line strategy for preventing GDM. A new study from Pennington Biomedical found that diet and exercise prescriptions are simply not working.

Diet and Exercise Doesn’t Reliably Prevent It

Jasper Most and colleagues followed 62 pregnant women with obesity. Their precision was painstaking. Most studies rely upon self-reports of eating and physical activity. However, these researchers carefully measured energy intake and expenditure. They used doubly labeled water to do it.

And that’s why they can say with confidence that energy balance made no difference in the risk of GDM. The women who developed it weren’t eating any more than the women who didn’t. Likewise, they were just as physically active. In other words, diet and exercise didn’t matter for preventing GDM.

A Need for Targeted Prevention?

Senior Author Leanne Redman explained that she sees a need for more targeted prevention strategies:

We and others now believe that there are different types of gestational diabetes that warrant different approaches to treatment and prevention.

Dr. Most agrees:

Preventing gestational diabetes is not as simple as reducing weight gain. It may require more individualized approaches based on each person’s risk factors.

Surprisingly Thin Evidence

GDM can be a serious complication of pregnancy. So it’s really somewhat shocking that we don’t know how to prevent it. Take a look at authoritative reviews for diet and exercise to prevent GDM and you’ll see. The evidence is thin – limited and very low quality.

Doctors tell pregnant women that diet and exercise will reduce their risk. However, it’s now pretty clear that’s not reliably true. Of course, a healthy diet and physical activity is important in pregnancy for many other reasons. It can prevent excessive weight gain. But it’s not the answer for preventing GDM.

The main risk factors for GDM are obesity and insulin resistance. So it’s no wonder that doctors might assume diet and exercise would help prevent it. Unfortunately it’s a shaky assumption. We can do better. We need genuinely effective prevention strategies for gestational diabetes.

Click here for the study and here for a patient perspective.

Pregnancy, photograph © Paladin27 / flickr

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January 11, 2019