It is estimated that 6% to 9% of pregnancies are complicated by diabetes; approximately 90% of which are gestational diabetes mellitus (GDM) (American College of Obstetricians and Gynecologists [ACOG], 2017). Gestational diabetes mellitus is carbohydrate intolerance during pregnancy leading to hyperglycemia. There are two categories: women who are able to achieve the glucose targets through lifestyle modification such as healthy eating and being active (GDMA1 or A1GDM); and women who require oral medication or insulin to lower their glucose values (GDMA2 or A2GDM) (ACOG). Women with GDM have a much higher likelihood of developing type 2 diabetes (T2DM), especially if they have a high body mass index or sedentary lifestyle. Despite these known risks, they are not always aware or counseled appropriately on self-care and implications for future health.

At around 37 weeks gestation, women should be taught about the long-term risk of developing T2DM after GDM and encouraged to get testing postpartum (Association of Women's Health, Obstetric and Neonatal Nurses [AWHONN], 2016). Benefits of early diagnosis, including prevention of recurrence and complications, can be discussed at this time. During the immediate postpartum period, the minimum recommendation is to check at least one fasting/premeal blood glucose (BG) with the desired result <100 mg/dL and a 1-hour postprandial BG after eating a "regular" nondiabetic diet with the goal of <140 mg/dL (AWHONN). Frequency and duration of standard postpartum testing may vary among institutions based on criteria including patients' risk factors and operative birth infection prevention. If a woman who had GDM has persistent hyperglycemia, continued testing is indicated with closer follow-up after discharge, continued home testing, and consideration of implementing medication therapy with insulin at half the third-trimester pregnancy dose or use of oral medication (such as metformin or glyburide) (AWHONN). Although encouraging breastfeeding is a common component of postpartum care, there are added diabetes-related benefits. Early breastfeeding can help stabilize newborn blood sugars, aid in maternal weight loss, and decrease risk of developing T2DM (when exclusively breastfeeding) (AWHONN).

Although GDM often resolves after birth, up to approximately 33% of women will have diabetes or prediabetes (impaired fasting glucose or impaired glucose tolerance) at their postpartum screening (ACOG, 2017). All women who had GDM (A1 and A2) should be screened at 4 to 12 weeks postpartum with a fasting plasma glucose followed by the 75 g, 2-hour oral glucose tolerance test (ACOG). Results of this screening place women into one of three categories: those with overt diabetes who should be referred for management of their disease; those with impaired glucose metabolism who should have consideration of a referral for management, weight loss and physical activity counseling, medical nutrition therapy, and/or medication therapy with yearly reassessment of glycemic status; or those in the normal range who should receive weight loss and physical activity counseling if indicated and assessment of glycemic status every 1 to 3 years, which may be done with the A1C lab test (ACOG; AWHONN, 2016).

All women who had GDM should be encouraged to follow up with a primary care provider who is made aware of the history of GDM (ACOG, 2017) to provide ongoing screening. By initiating prevention and/or treatment, women can potentially delay the onset of T2DM, prevent GDM or adverse outcomes in subsequent pregnancies, and prevent complications from the disease (AWHONN, 2016). Refrain from implying that women are "cured" of their GDM after they have given birth. Many of the diet and exercise recommendations should be encouraged to be continued including 30 minutes of exercise per day, especially in patients in whom weight loss should be a goal. Exercise, weight loss, and healthy eating, especially when combined together, can have many long-term benefits (AWHONN). It is essential that women who have been diagnosed with GDM receive appropriate information about its long-term implications and what they can do to minimize risks of future health problems.

References