Effects of Bariatric Surgery on Maternal and Infant Outcomes of Pregnancy-An Evidence Analysis Center Systematic Review

Background While obesity presents specific acute and long-term risks to the pregnant woman and her offspring, the effects of bariatric surgery on pregnancy outcomes are undetermined. Objective A systematic review was performed according to the Academy of Nutrition and Dietetics Evidence Analysis Library process to determine the effects of bariatric surgery on both maternal and infant health outcomes of pregnancy. Design A comprehensive literature search of PubMed was conducted to identify studies published from years 2000 to 2015 that examined the health effects of pregnancy after bariatric surgery. Experimental studies and observational studies with a control group were included. Main outcome measures Outcomes of interest were gestational weight gain, maternal complications (ie, gestational diabetes, preeclampsia, eclampsia, hypertension, and postpartum hemorrhage), miscarriage and/or stillbirth, cesarean section, birth weight in grams, birth weight in categories (ie, macrosomia, low birth weight, small for gestational age, and large for gestational age), gestational age and preterm birth, infant illness and complications (ie, perinatal death, admission to neonatal intensive care unit, neonatal illness, and congenital malformation rates), and Apgar scores. Results Thirteen of 246 studies were included. Compared to body mass index-matched controls without surgery, bariatric surgery before pregnancy reduced infant birth weight in grams, with no effect on total maternal gestational weight gain or Apgar scores. Surgery did not increase risk of adverse outcomes, such as miscarriage and/or stillbirth, preterm birth, or infant complications. Effects of surgery on maternal complications, infant birth weight categories, and surgical delivery rates were inconsistent. Conclusions Bariatric surgery is a successful treatment of maternal obesity, but certain surgery-specific risks may exist. More data are needed to determine clinical guidelines. The long-term effects of surgery on pregnancy outcomes are unknown.