Optimal range of gestational weight gain for singleton pregnant women: a cohort study based on Chinese specific body mass index categories

Background The purpose was to explore the optimal proportion of GWG in Chinese singleton pregnant women according to Chinese specific body mass index (BMI) categories.Methods A retrospective cohort study with 16,977 singleton pregnant women was conducted. Among the including subjects, 2/3 of which were randomly imported into the training set for calculating the optimal GWG ranges using the percentile method, the Odd Ratio (OR) method, and the combined risk curve method. And another third of the subjects were used to evaluate the GWG ranges obtained. The detection rate of adverse outcomes of pregnant women was used to evaluate the applicability of GWG obtained. The range corresponding to the lowest detection rate is the recommended GWG range in this study.Results According to the percentile method, the suitable GWG of pregnant women with underweight, normal weight, overweight or obesity before pregnancy were 12.0 similar to 17.5 kg, 11.0 similar to 17.0 kg, and 9.0 similar to 15.5 kg, respectively. According to the OR method, the suitable GWG range were 11 similar to 18 kg, 7 similar to 11 kg, and 6 similar to 8 kg, respectively. According to the combined risk curve method, the suitable GWG range were 11.2 similar to 17.2 kg, 3.6 similar to 11.5 kg, and - 5.2 similar to 7.0 kg, respectively. When the GWG for different BMI categories were 11 similar to 18 kg, 7 similar to 11 kg, and 6 similar to 8 kg, the pregnant women have the lowest detection rate of adverse maternal and infant outcomes.Conclusions The recommended GWG based on this study for underweight, normal, overweight or obese pregnant women were 11 similar to 18 kg, 7 similar to 11 kg, and 6 similar to 8 kg, respectively.