Final answer:
Prolactin from the anterior pituitary stimulates milk production after a woman gives birth. When the baby begins suckling at the breast, signals are sent to the hypothalamus causing the release of prolactin. Prolactin causes the mammary glands to produce milk.
Step-by-step explanation:
Prolactin from the anterior pituitary stimulates milk production after a woman gives birth. Prolactin levels are regulated by the hypothalamic hormones prolactin-releasing hormone (PRH) and prolactin-inhibiting hormone (PIH), which is now known to be dopamine. PRH stimulates the release of prolactin and PIH inhibits it.
When the baby begins suckling at the breast, signals are sent to the hypothalamus causing the release of prolactin from the anterior pituitary. Prolactin causes the mammary glands to produce milk. Oxytocin is also released, promoting the release of the milk.
The mother's mammary glands go through changes during the third trimester to prepare for lactation and breastfeeding. Prolactin stimulates the production of milk by the mammary glands following childbirth.