Since obesity in women increases risk of cardiovascular disease, diabetes, breast cancer, gall bladder disease, and osteoarthritis, identifying factors that affect weight retention after pregnancy is important.
Past studies looking at the effects of breast-feeding on postpartum weight change are inconclusive.
At each visit, the staff interviewed the women about their infant feeding practices, the mother's diet during the previous 6 months using a food frequency questionnaire, physical activity, and reproductive history. The main outcome was postpartum weight retention, calculated by subtracting the weight before pregnancy from the woman's weight at each postpartum visit. The average weight dropped from 67.2 kg to 62.4 kg over the entire 18 months. Physical activity was lowest at the 2 week postpartum visit. However, after that point, activity levels did not vary over the 18 months.