Primary Care Department, Touro University California connie.ha@tu.edu
Dr. Shubrook reported serving as a consultant or advisor to Abbott, AstraZeneca, Bayer, Lilly, and Novo Nordisk. The other authors reported no potential conflict of interest relevant to this article.
Sulfonylureas are no longer recommended because of the risk of maternal and fetal hypoglycemia and concerns about this medication crossing the placenta.24,31,32 Specifically, in a 2015 meta-analysis and systematic review of 15 articles (n = 2509), glyburide had a higher risk of neonatal hypoglycemia and macrosomia than insulin or metformin.33 For women who cannot manage their glucose with therapeutic lifestyle changes and cannot take insulin, oral therapies may be considered if the risk-benefit ratio is balanced for that person.34
Watch for effects of poor glycemic control on mother, infant
Preeclampsiais defined as new-onset hypertension and proteinuria after 20 weeks of gestation. The correlation between GDM and preeclampsia has partly been explained by their shared overlapping risk factors, including maternal obesity, excessive gestational weight gain, and persistent hyperglycemia.35 On a biochemical level, these risk factors contribute to oxidative stress and systemic vascular dysfunction, which have been hypothesized as the underlying pathophysiology for the development of preeclampsia.35
Neonatal macrosomia,defined as a birth weight ≥ 4000 g, is a common complication that develops in 15% to 45% of infants of mothers with GDM.36 Placental transfer of glucose in mothers with hyperglycemia stimulates the secretion of neonatal insulin and the ultimate storage of the excess glucose as body fat. After delivery, the abrupt discontinuation of placental transfer of glucose to an infant who is actively secreting insulin leads to neonatal hypoglycemia, which if not detected or managed, can lead to long-term neurologic deficits, including recurrent seizures and developmental delays.37 Therefore, it is essential to screen for neonatal hypoglycemia immediately after birth and serially up to 12 hours.38
Postpartum T2D.Poor glycemic control increases the risk of increasing insulin resistance developing into T2D postpartum for mothers.39 It also increases the risk of obesity and insulin resistance later in life for the infant.40 A retrospective cohort study (n = 461) found a positive correlation between exposure to maternal GDM and elevated BMI in children ages 6 to 13 years.41 Kamana et al36 further discussed this correlation and suggested that exposure to maternal hyperglycemia in utero contributes to fetal programming of later adipose deposition. Children may develop without a notable increase in BMI until after puberty.42
Partner with specialists to improve outcomes
Although most women with GDM are managed by specialists (obstetricians, endocrinologists, and maternal-fetal medicine specialists),43 these patients are still seeking care from their family physicians for other complaints. These visits provide key touchpoints during pregnancy and are opportunities for PCPs to identify a pregnancy-related complication or provide additional education or referral to the obstetrician.
