Does infant feeding method influence maternal postpartum weight loss?

We conducted a retrospective study of 411 women to determine whether a significant relationship existed between method of infant feeding (breast vs bottle) and postpartum weight loss at 6 weeks and 12 months. In addition to method of infant feeding, the variables parity, gravidity, mode of delivery, maternal age, maternal prepregnancy weight, infant sex, and payment status (whether receiving assistance from the Aid to Dependent Children [ADC] program) were studied in terms of their association with weight loss. In general, no consistent relationship was found between method of infant feeding and postpartum weight loss. However, in the ADC group at 6 weeks and in the non-ADC group at 12 months, nonlactating women had lost more weight than had their lactating counterparts, in spite of the theoretical energy deficiency of breast-feeding women. Women who gained more weight during pregnancy consistently lost more weight following delivery, regardless of their prepregnancy weight. These results indicate that infant feeding method was not related to differences in postpartum weight loss between lactating and nonlactating counterparts.