OBJECTIVETo investigate the relationship of pre-pregnancy body weight, gestational weight gain and postpartum weight retention among women in Beijing.

METHODSUsing a cohort design, 600 pregnant women who went to district obstetrics and gynecology hospital in Beijing to establish preconception health care card from 5(th) February to 15(th) March 2009 were recruited. A total of 112 subjects (109 with valid data), 20% of that in baseline, were followed up at 6 months after delivery.70 subjects (66 with valid data) were followed up at one year after delivery. Weight, weight changes and postpartum weight retention were measured for low weight (BMI < 18.5 kg/m(2)), normal weight (18.5 kg/m(2) ≤ BMI ≤ 24.0 kg/m(2)) and overweight or obesity (BMI > 24.0 kg/m(2)) group.

RESULTSThe pre-pregnancy weight and antenatal weight were (54.8 ± 8.0) and (70.8 ± 9.3) kg respectively. Gestational weight gain was (16.0 ± 7.0) kg. The postpartum weight of 6 and 12 months were (60.5 ± 9.4) and (57.6 ± 8.6) kg respectively. Comparing to pre-pregnancy, postpartum weight retention in 6 months and 12 months were (5.7 ± 4.5) and (2.7 ± 4.5) kg, weight retention rates were (10.6 ± 8.6)% and (5.2 ± 9.3)%. Antenatal weight among low pre-pregnancy weight group, normal weight and overweight and obese women were (62.6 ± 5.7), (69.9 ± 6.6) and (84.2 ± 9.9) kg, and weight at postpartum 12 months among 3 groups were (49.3 ± 3.2), (56.5 ± 6.9) and (70.5 ± 6.0) kg respectively (F = 25.3, P < 0.01); At postpartum 12 months, low pre-pregnancy weight group ((5.6 ± 5.9) kg), overweight and obese women group ((4.7 ± 1.9) kg) postpartum weight retention was significantly higher than that of the normal weight group ((1.8 ± 4.3) kg) (F = 3.82, P < 0.05).

CONCLUSIONThe pre-pregnancy body weight is a key risk factor in weight gain during pregnancy and postpartum weight retention.