Changes In Body Composition During The Postpartum Period

The common belief: that lactating women experience greater weight and fat loss than their non-lactating counterparts during the postpartum period has often been cited by pregnant women as an advantage of breastfeeding. We classified 28 women, aged 21 to 39. years, into 5 groups according to length of lactation. Group 1 consisted of 5 women non-lactating women. Group 2 breastfed solely 1-3 months and consisted of 5 women. Nine women were in group 3 whom breastfed solely 4-6 months. Group 4 consisted of 4 women who breastfed solely 7-9 months, and group 5 consisted of 5 women who: breastfed solely 10-12 months. Body composition measurements were taken at 1, 2, 3, 6, and 12 months postpartum and included body weight; percent body fat; bicep and tricep skinfold thickness; and maternal energy intake and expenditure. A steady but significant decline in mean maternal body weight occurred in all groups over the 12 month postpartum period (p=0.008); however, there were no significant differences between the 5 groups (p=0.703). Likewise, the percent body fat resulted in a significant decrease for all groups (p=0.005), while there was no significant difference between the groups (p=0.513). The bicep and tricep skinfold thickness did not change significantly between the groups during the 12 month postpartum period (p=0.688 and p=0.434 respectively). The calculated energy intake did not change significantly between groups during the 12 month postpartum period (p=0.139). In fact, the mean caloric level of all groups never actually reached the RDA level for non-pregnant, non-lactating females. Furthermore, the estimates of energy expenditure for maintenance and activity did not differ between the groups (p=0.564). These results do not support the cannon belief that breastfeeding facilitates greater weight loss in the postpartum period.