Pregnancy in Women With Obesity

About half of women delivering a liveborn neonate are overweight (25.6%) or obese (24.8%) before pregnancy. From 2011 to 2015, the distribution of women experiencing obesity shifted toward a higher body mass index (BMI), where the greatest rise was seen in BMIs >40 kg/m2 (14% increase). Obesity is associated with significant pathophysiologic changes, including chronic inflammation and insulin resistance, that contribute to adverse pregnancy outcomes. As BMI increases, so do the risks of preexisting hypertension and diabetes, subfertility, congenital anomalies, stillbirth, preeclampsia, gestational diabetes, sleep apnea, cesarean delivery, wound complications, thromboembolic events, macrosomia, postpartum weight retention, and childhood obesity. Excess gestational weight gain is an independent predictor of macrosomia and postpartum weight retention. Bariatric procedures tend to improve overall risks during pregnancy but can be associated with micronutrient and vitamin deficiencies and fetal growth restriction. Though some strategies can be employed to mitigate these risks, additional research is needed to identify interventions that improve maternal and fetal well-being in individuals with obesity.