Childbirth and Perinatal Outcomes of Healthy, Low-risk Pregnant Women With Abnormal Total Gestational Weight Gain.

Abstract PurposeLittle is known on the potential effects of abnormal GWG among low-risk, healthy pregnant women with no comorbidities or gestational complications.We investigated perinatal outcomes of these pregnancies according to GWG as per the 2009 National Academy of Medicine (NAM) recommendations.MethodsA retrospective analysis of prospectively collected data of low-risk pregnant women giving birth after 370/7 weeks’ gestation at our center between 1/2016 and 12/2020. Only women with normal pregestational BMI (pBMI) (18.5-24.9 Kg/m2) and no pre- or gestational complications were included. Self-reported prepregnancy weight was used to calculate pBMI; GWG was the difference between maternal weight at childbirth and prepregnancy weight. Women were classified according to the 2009 NAM guidelines for GWG: insufficient (iGWG, 16 Kg). Logistic regression analysis with aGWG as referent was performed to independent estimate dose-response associations.ResultsDuring the study period, there were 4,127 (33.1%) births fulfilling the inclusion criteria. Fifty-two percent of women gained outside the recommended range: 33.5% had iGWG and 18.7% eGWG. iGWG women were 40% more likely to have early-term births and SGA neonates. In turn, eGWG women displayed increased odds of prolonged pregnancy (aOR 1.32), cesarean section in labor (aOR 1.50), high-degree perineal tears (aOR 2.04, postpartum hemorrhage >1000 mL (aOR 1.54), and LGA newborns (aOR 1.83).ConclusionOur data show that abnormal GWG can independently associate with heightened risk of adverse outcomes among healthy, low-risk pregnant women with normal pBMI and no comorbidities or gestational complications.