When I first meet a woman who is pregnant and newly diagnosed with gestational diabetes (GDM), she often expresses a multitude of emotions including guilt, annoyance, and fear. She may have been misinformed about the condition from unreliable sources in her community and the internet. 

It is always a perfect time to talk about some key facts about gestational diabetes. It is my hope that this will empower a woman with the knowledge she needs to best take care of herself and her baby.

1. What is GDM?

Gestational diabetes is a disorder, similar to diabetes mellitus (DM), that affects how the body processes sugar. Insulin, which is made by the pancreas, plays a major role in preventing excessive blood sugar amounts to build up in the blood. All pregnant women are naturally resistant to the effects of insulin; this insulin resistance increases as the pregnancy advances. In pregnancy, the pancreas will make more insulin to overcome the natural resistance, but for women who have GDM, their body does not make enough insulin to lower her blood sugar to a safe amount.

2. How common is gestational diabetes?   

About three to eight percent of all pregnant women in the U.S. are diagnosed with GDM. A woman is more likely to develop GDM if she:

  • Is overweight
  • Had prediabetes when not pregnant or gestational diabetes in a prior pregnancy
  • Has family members with diabetes
  • Is over the age of 25
  • Is African-American, American Indian, Asian American, Hispanic or Latino, or Pacific Islander.

3. How does GDM affect the pregnancy? 

A baby exposed to high blood sugar levels is at risk for excessive weight gain (macrosomia). This can make delivery difficult and potentially cause injury to mother and baby. The baby’s metabolism can also be affected and the newborn can experience low blood sugar (hypoglycemia) soon after birth. Mothers with GDM also have an increased risk for pre-eclampsia (a potentially dangerous complication during pregnancy that can cause high blood pressure, kidney problems and more). 

4. What is the treatment for gestational diabetes? 

To keep a mother’s blood sugar in the normal range, her treatment may include:

  • A special diet
  • Exercise
  • Daily blood glucose monitoring
  • Insulin injections

Insulin does not cross the placenta—so the baby is not exposed to the medication—and is safe to use when prescribed in pregnancy. 

5. What happens after the pregnancy? 

Most of the time the insulin resistance resolves after birth and the mother can discontinue her GDM treatment. She still has a high risk for developing diabetes mellitus in the future and needs to have repeat diabetes screening (first done at six to eight weeks after birth). Mothers can decrease their risk for future GDM and DM by breastfeeding and with lifestyle changes to achieve or maintain a healthy weight through diet and exercise. 

Courtney Clark Bilodeau, MD, FACP

Dr. Courtney Clark Bilodeau is a physician in obstetric medicine at the Women's Medicine Collaborative, with clinical and research interests that include breastfeeding, evidence-based complementary medicine, and peripartum management of chronic medical conditions from preconception through postpartum.