The mean postpartum weight retention in Thai singleton pregnant women with normal pre-pregnancy BMI is 4.99 ± 4.03 kg. The numeric factors (age, height, pre-pregnancy weight, pre-pregnancy BMI, gestational weight gain and birth weight) are summarized in Table 1. Gestational VOL. 16, NO. 4, OCTOBER 2008 Theananasuk M et al. Postpartum weight retention in Thai singleton 223 pregnant women with normal pre-pregnancy body mass index weight gain during pregnancy has a consistent positive relationship to postpartum weight retention