What is the primary hormone responsible for milk production after childbirth?

The primary hormone responsible for milk production after childbirth is prolactin. This hormone is secreted by the anterior pituitary gland and plays a crucial role in initiating and maintaining lactation. After a woman gives birth, prolactin levels increase significantly, stimulating the mammary glands to produce milk.

While other hormones like estrogen, oxytocin, and progesterone play important roles during pregnancy and in the breastfeeding process, they do not directly stimulate milk production. Estrogen promotes the development of breast tissue during pregnancy, progesterone supports the maintenance of pregnancy, and oxytocin is key for milk ejection during nursing, but it is prolactin that is primarily responsible for the synthesis of milk. Understanding the distinct roles of these hormones is vital for grasping how breastfeeding functions post-delivery.