Socio-demographic determinants of pre-pregnancy body mass index and gestational weight gain

Both pre-pregnancy body mass index (BMI) and gestational weight gain (GWG) are important determinants of a healthy pregnancy outcome and may show important variation. To study the influence of socio-demographic and obstetrical correlates on pre-pregnancy BMI and GWG, data of 54 022 singleton term pregnancies were analysed using adjusted regression models. In 2009, in the Northern region of Belgium, one-third of women were overweight (21.6%) or obese (10.1%) and GWG as recommended by the Institute of Medicine occurred in only 28% of obese women. A high pre-pregnancy BMI was significantly associated with low maternal education, high maternal age and multiparity, belonging to ethnic minority groups and a lower professional state. Compared to adequate GWG, excessive GWG was more common in younger (