Patient’s characteristics and their pregnancy outcomes are presented as percentage, mean with standard deviation (SD) or median with interquartile range (IQR). Patients were divided into four groups according to their pre-pregnancy BMI. Gestational weight gains of each group are reported and compared using median with IQR and Kruskal–Wallis test, respectively. The optimal gestational weight gain for each group was proposed to achieve a high proportion of appropriatefor-gestational-age (AGA) fetuses. The comparison of patients’ characteristics and pregnancy outcomes were analyzed using the Wilcoxon rank–sum test for continuous variables and Pearson’s χ2-test for categorical variables.