THE RELATIONSHIP BETWEEN WEIGHT-GAIN IN PREGNANCY, BIRTH-WEIGHT AND POSTPARTUM WEIGHT RETENTION

A total of 292 middle class, nonsmoking Chinese patients with known pr epregnant weight who subsequently had uncomplicated singleton pregnanc ies delivering after 36 weeks' gestation were recruited to assess thei r serial antenatal weight gain, weight at 6 weeks and 3 months postpar tum. The average prepregnant body mass index in the whole group was 20 .4 kg/m(2) (SD 2.19), and the total pregnancy weight gain was 14 kg (S D 3.75). Those with weight gain over 17.83 kg (one SD above the mean) (n=58) had higher weight gain in all 3 trimesters taken separately, as well as higher weight retention at 6 weeks and 3 months postpartum (p <0.001). Similar differences were noted for those with total weight g ain over 2 standard deviations above the mean. The average weight reta ined at 3 months postpartum was 3.64 kg (SD 2.75). Those with weight r etention over 9.14 kg (2 SD above the mean) (n=8) had a significantly higher second and third trimester weight gain (p <0.01) compared to th e rest. These data suggest that excessive weight gain during pregnancy for women with prepregnant BMI in the normal range occurred most sign ificantly after the mid-trimester, and was associated with higher post partum weight retention without significant increase in birth-weight.