The effect of leptin concentrations and other maternal characteristics on gestational weight gain is different according to pre-gestational BMI: results from a prospective cohort

ObjectiveTo evaluate the effect of leptin and other selected variables on gestational weight gain (GWG) according to pre-gestational body mass index (BMI). DesignProspective cohort. SettingPublic Health Center, Rio de Janeiro, Brazil. SampleTwo hundred and twenty-eight pregnant women. MethodsWomen were followed at the 5-13, 20-26 and 30-36th gestational weeks. The effects of independent variables on GWG in normal weight (BMI 18.5-24.9kg/m(2)), overweight (BMI 25.0-29.9kg/m(2)) and obese (BMI30.0kg/m(2)) women were assessed using longitudinal linear mixed-effects models. Main outcome measureMaternal body weight (kg) throughout pregnancy. ResultsLeptin concentrations were associated with GWG in normal weight (=0.048, P<0.001) and overweight (=0.023, P=0.048) women, but not in obese ones (=0.011, P=0.308). Additionally, the number of hours slept per night decreased the effect of leptin on GWG in OW women (=-0.013, P=0.002). The effect of other maternal characteristics on GWG was different depending on the BMI category. ConclusionsLeptin concentrations were positively associated with GWG in normal weight and overweight women, but not in obese ones. Maternal height was associated with GWG in all BMI categories, but other variables such as sleep duration, QUICKI values, HDL-c, smoking habit and marital status presented differential effects according to BMI. We encourage further studies to investigate the association between leptin and gestational weight gain, taking into account the pre-pregnancy weight and sleep duration, in order to compare and confirm our results. Tweetable abstractLeptin is associated with weight gain in normal weight and overweight pregnant women, but not in obese ones. Tweetable abstract Leptin is associated with weight gain in normal weight and overweight pregnant women, but not in obese ones.