RESUMO
OBJECTIVES: Inadequate gestational weight gain (GWG) has been associated with low birth weight (LBW). However, factors associated with inadequate GWG in Japan remain unclear. Here, we aimed to determine the factors associated with inadequate GWG and the characteristics of inadequate GWG based on the pre-pregnancy body mass index (BMI) among pregnant women in Japan. METHODS: This observational study included pregnant women at ≥16 weeks of gestation. The study was conducted at two general hospitals in Tokyo, Japan. The participants were requested to complete a questionnaire during the antenatal checkup visit and a mail survey after childbirth. Data were also collected from medical records. The GWG level and associated factors were assessed using the chi-square test or t-test. RESULTS: In total, 252 pregnant women were recruited and completed the questionnaires. Data from 128 pregnant women were analyzed. Overall, 23 (18.0%) women were classified as having inadequate GWG. The factors associated with inadequate GWG were as follows: pre-pregnancy underweight, hospital admission owing to hyperemesis, low body esteem, high Edinburgh Postnatal Depression Scale score, low target GWG, more significant weight loss during pregnancy when compared with that pre-pregnancy, high maximum weight loss during pregnancy, delay in return to pre-pregnancy weight, lower birth weight, and inadequate GWG perception. Pregnant women with inadequate weight gain did not receive any medical advice to avoid being overweight but were rather advised to gain additional weight. CONCLUSION: Target GWG and low body esteem were associated with inadequate GWG and other factors that could be modified. Medical staff should focus on achieving the target GWG and improving the body appreciation level among pregnant women.