Almost one of every ten pregnant women will develop gestational diabetes mellitus (GDM), which usually strikes during the second trimester. Gestational diabetes can affect the baby as well as the pregnancy. Although GDM usually resolves itself shortly after childbirth, it has a lingering effect: Women who have GDM are at greater risk of developing type 2 diabetes the rest of their lives.
A recently published study indicates a woman can reduce her risk of type 2 diabetes after GDM by taking aggressive preventive measures that include lifestyle changes and treatment with metformin, a drug that suppresses glucose production in the liver. Metformin is the drug of choice for treating type 2 diabetes but it is not safe to take during pregnancy. For the best outcome, these protective measures should be started as soon after pregnancy as possible.
The Diabetes Prevention Program Outcomes Study involved more than a thousand mothers under treatment at 27 clinics. The women were medically evaluated at the time they volunteered for the study and they were followed for the next ten years:
- 288 women had had GDM
- 1,226 had live births with no history of GDM
- All were overweight or obese
- All tested to be in a pre-diabetic state (impaired fasting glucose and impaired glucose tolerance)
The study participants were randomly assigned one of three interventions:
- Treatment with metformin.
- Treatment with placebo (a drug with no therapeutic effects used to assess the psychological influence on physical health).
- Intensive lifestyle (ILS) changes which included reduction of body weight by 7% and 150 minutes each week of moderate cardio exercise.
Ten years later, at the end of the study, the outcomes included:
- 48% higher risk of developing type 2 diabetes in women with GDM history assigned to the placebo group than the women with no GDM history also taking a placebo.
- 40% lower risk of type 2 in women with GDM history in the metformin group.
- 35% lower risk of type 2 in women with GDM history in the ILS group.
- 30% lower risk of type 2 in women with no GDM history in the ILS group.
- No change in risk of type 2 in women with no GDM history who took metformin.
The women who had had GDM significantly reduced their risk of type 2 diabetes for a 10-year period by either taking metformin or undergoing aggressive lifestyle changes. Women who had not developed GDM during pregnancy significantly reduced their risk of developing type 2 diabetes by aggressive lifestyle changes alone. Metformin was not an effective preventive measure for these women.
- "Interventions Lower Diabetes Risk in Women who had Gestational Diabetes." Endocrine Society. Endocrine Society, 23 Feb. 2015. Web. 16 Mar. 2015.
- "Gestational Diabetes (.pdf)." CDC. National Center for Chronic Disease Prevention and Health Promotion, n.d. Web. 16 Mar. 2015.