Effect of Gestational Weight Gain on Perinatal Outcomes in Low Risk Pregnancies with Normal Prepregnancy Body Mass Index

OBJECTIVE: This study aimed to clarify the effect of gestational weight gain (GWG) on perinatal outcomes in low risk pregnancies with normal prepregnancy body mass index (BMI). STUDY DESIGN: A total of 572 low-risk pregnant women with a normal prepregnancy BMI were included. GWG and inadequate or excessive weight gain were defined according to the United States Institute of Medicine updated guidelines. Adverse perinatal outcomes were compared among inadequate, normal, and excessive weight gain groups. RESULTS: Of the 572 pregnant women enrolled, 62 belonged to inadequate GWG group, 80 to excessive GWG group, and 430 to normal GWG group. Maternal age, prepregnancy BMI, gravity, parity, and previous cesarean delivery rates were similar among groups. Adverse perinatal outcomes were not statistically significant among groups. Fetal weight was significantly lower in inadequate weight gain group compared to normal weight gain group (p<0.001) and fetal weight was significantly lower in normal weight gain group compared to excessive weight gain group (p<0.001). Additionally, low birth weight <2.5kgs, birth weight > 4.0kgs, and SGA and LGA rates were similar among groups (P = 0.765, P = 0. 711, P = 0. 702, and P = 0.414, respectively). Although gestational age at delivery was term in normal percentile it was significantly lower in the inadequate weight gain group compared to others (P=0.010). CONCLUSIONS: This study showed that an inadequate or excessive weight gain in low-risk pregnancies with a normal prepregnancy BMI did not increase the risk of adverse perinatal outcomes.