Nursing her baby causes the mother's body to release oxytocin, which stimulates contractions which help shrink the uterus back to prepregnancy size while expelling the placenta. These contractions also shut off the maternal blood vessels that formerly fed the baby and discourage excessive bleeding. Women who choose not to breastfeed must be given synthetic oxytocin to insure against hemorrhaging. Chua S, Arulkumaran S, Lim I et al. Influence of breastfeeding and nipple stimulation on postpartum uterine activity.
Nursing helps mom lose weight after baby is born.
Breastfeeding requires an average of 500 extra calories per day. Maternal weight-loss patterns during prolonged lactation. Pre-term milk is specially designed for premature infants. Milk produced by women who deliver prematurely differs from that produced after a full-term pregnancy. Specifically, during the first month after parturition, preterm milk maintains a composition similar to that of colostrum.