Restricting weight gain during pregnancy in Japan: A controversial factor in reducing perinatal complications

Objective: To evaluate the effectiveness of restricting weight gain during pregnancy to reduce perinatal complications. Study design: The study was conducted in the Tokyo metropolitan area, and reviewed 3071 mothers and their infants born from singleton pregnancies retrospectively. To examine the influence of increased maternal weight gain on perinatal complications, we performed five-category stratification for weight gain: less than 8.0, 8.0-10.0, 10.1-12.0, 12.1-14.0 and over 14.0 kg. Results: Total weight gains less than 8.0 kg significantly increased the risk of low birth weight (LBW) and small for gestational age (SGA) infants (OR = 2.19, 95% CI; 1.36-3.52, OR = 1.76, 95% CI; 1.23-2.51) and total weight gain over 14.0 kg significantly increased the risk of large for gestational age (LGA) infants and pregnancy induced hypertension (PIH) (OR = 3.06, 95% CI; 1.88-4.98, OR = 2.87, 95% CI; 1.86-4.42, respectively), compared with women with weight gain of 10.1-12.0 kg. The groups with weight gains of 8.0-10.0 kg and 12.1-14.0 kg did not show adverse perinatal outcomes, including gestational diabetes (GDM), cesarean delivery, postpartum hemorrhage and laceration, significantly different from the 10.1 to 12.0 kg gain group. Conclusion: Strict restriction of weight gain during pregnancy is not effective in reducing perinatal complications.