GESTATIONAL DIABETES MELLITUS (GDM)

Gestational diabetes mellitus (GDM), defined as diabetes diagnosed in second and third trimesters of pregnancy.

In India alone, GDM complicates nearly 4 million pregnancies annually, representing a large subset of the population at high risk for adverse perinatal morbidity and mortality if left inappropriately managed. As substantiated by “fetal origin of adult disease” hypothesis, the perpetuation of this ongoing cycle needs to check to avoid the occurrence of unfavorable consequences in future generations.

Risk Factors for GDM

• Obesity
• Previous history of GDM
• Prior delivery of a large baby (> 4 kg or >9 lbs)
• Family history of diabetes in a first-degree relative

Complications of Diabetes in Pregnancy

Maternal Complications:

Gestational hypertension preeclampsia is a common complication of pregnancy complicated by diabetes.

Other maternal complications during pregnancy include hypoglycemia, infection (eg, pyelonephritis), ketoacidosis, polyhydramnios, preterm labor, and seizures. The risk of spontaneous abortion in diabetic pregnancies has been reported to be between 30% and 60% twice that of the general population.

Pregnant women with GDM has an increased risk of future T2DM. Between 5% and 10% of women with GDM develop T2DM immediately post-pregnancy. Furthermore, women with a history of GDM have a 35% to 60% chance of developing T2DM over the subsequent 10 to 20 years.

Diet Recommendations:

• Avoid large meals and foods with a high percentage of simple carbohydrates
• Patients should be counseled on healthy low-carbohydrate, high-fiber sources of nutrition, as well as the importance of avoiding sugars, simple carbohydrates, and highly processed foods.
• Restriction of carbohydrates to 35% to 40% of total caloric intake has been found to decrease maternal glucose levels and improve outcomes for both mother and child.
• Fresh vegetables are the preferred carbohydrate sources for pregnant women with diabetes.
• Consumption of dairy products should be limited; juices and most fruits should be avoided altogether.
• Consumption of frequent small meals to reduce the risk of postprandial hyperglycemia and preprandial starvation ketosis.

Postpartum Care and Lactation

Postpartum care should include psychosocial assessment and support for self-care.

Since metformin and glyburide are secreted into breast milk, these medications should not be used by women who are breastfeeding.

Breastfeeding may lead to severe hypoglycemia in women who are receiving insulin therapy; this risk is greatest in those with T1DM. Preventive measures include a reduction in basal insulin dosage and/or carbohydrate intake prior to breastfeeding.

A 2-hour 75-g OGTT is recommended at 6 to 8 weeks postpartum and at 1 year in patients with GDM. If within normal limits, measurement of A1C yearly and OGTT every 3 years is recommended.