Your body releases oxytocin when your baby is nursing. (mymilkybaby.com)
While breastfeeding your baby the body also releases oxytocin hormone that also has a negative influence on the reproductive cycle. (themamaneeds.com)
It's important to feel relaxed and comfortable when you're expressing or breastfeeding as it is believed to help by releasing oxytocin, the hormone that stimulates milk production. (charlottekeating.com)