Gestational Weight Gain, Weight Retention and Risk to Develop Overweight and Obesity in Rural Guatemalan Women

Abstract

Data from the INCAP longitudinal study and 1996-1999 follow-up were used to explore the association of total and timing of gestational weight gain (GWG) with postpartum weight retention (PWR) and the risk of developing overweight and obesity at 6 months postpartum in rural Guatemalan women. The contribution of genetics to the variability of GWG was also explored. Total and timing of GWG and postpartum weight retention: Women with a pre-pregnancy BMI < 30 kg/m2 retained more weight with increasing GWG. We also found that for women who started pregnancy overweight (BMI = 25-29.9 kg/m2) for every month of predominantly exclusive breastfeeding, the PWR at 6 months decreased by 0.8 kg (p< 0.0001), whereas in women who started pregnancy with BMI < 25 kg/m2 there was no association between breastfeeding practices and weight retention (Interaction p-value= 0.03). The PWR at 6 months was associated with late GWG, but not with early GWG. Late GWG of 100 g/wk or 2.0 kg for the last half of pregnancy was associated with an increase 1.0 kg in PWR at 6 months. Total and timing of GWG and risk of becoming overweight and obese at 6 months postpartum: After adjusting for initial BMI and breastfeeding practices, the risk of becoming overweight by six months postpartum increased by 40% for every kg of net GWG in women with pre-pregnancy BMI between 20 and 24.9 kg/m2, and the risk of becoming obese increased by 200% for every kg of net GWG in women with pre-pregnancy BMI between 25 and 29.9 kg/m2. The risk of becoming overweight was reduced in women with the most intensive breastfeeding patterns. The late GWG, but not early GWG, was associated with greater risk of becoming overweight at 6 months postpartum. Heritability of weight change during pregnancy: Our analysis lacked statistical power to test whether weight change during pregnancy is inherited. Studying whether the high variability in weight change during pregnancy has a genetic basis is of clinical and public health interest thus better approaches to address the question need to be explored.