ARE OVERWEIGHT WOMEN AT INCREASED RISK OF OBESITY FOLLOWING PREGNANCY

Longitudinal studies suggest that women who already have a high BMI ar e at greater risk of maternal obesity than their lighter counterparts. The aim of the I,resent study was to investigate this possibility by examining the relationship between reproductive history and maternal B MI in a community of 627 women from South Africa with a high prevalenc e of obesity. Standardized questionnaires were used to obtain detailed sociodemographic and behavioural information, while maternal weight a nd height were both measured at the time of the interview. Analysis of covariance (ANCOVA) showed that maternal age (r(2) 0.015, P = 0.001), smoking status (r(2) 0.012, P = 0.036), and social support (r(2) 0.01 1, P = 0.006) were all independently associated with maternal BMI. If overweight women were at increased risk of maternal obesity, then the positive relationship between reproductive history and maternal BMI sh ould be enhanced in this relatively obese community, yet the ANCOVA mo dels showed no independent association between gravidity and maternal BMI after controlling for the effects of confounding factors. Although previous longitudinal studies have found a positive association betwe en prepregnant weight and long-term weight gain, this relationship mig ht arise because overweight women gain more weight over a fixed period of time than normal weight women, and therefore they may appear to be at greater risk of pregnancy-related weight gains. Overweight women a re at greater risk of weight gain generally, but there is little unequ ivocal evidence to suggest that they are at any increased risk of mate rnal obesity, when compared with women of lower BMI.