What hormone stimulates milk production in breastfeeding mothers?

• A. Estrogen
• B. Prolactin
• C. Oxytocin
• D. Progesterone

Answer: (B)

Prolactin is the hormone responsible for stimulating milk production in breastfeeding mothers. This hormone is secreted by the anterior pituitary gland and plays a crucial role during and after pregnancy by promoting lactogenesis, which is the process of milk production. Prolactin levels rise during pregnancy, preparing the mammary glands for milk secretion, and they continue to be elevated in response to the infant's suckling.

Estrogen contributes to breast development and prepares the breasts for lactation but does not actively stimulate milk production. Oxytocin, another important hormone in breastfeeding, is primarily involved in the milk let-down reflex, facilitating the release of milk that has been produced due to prolactin. Progesterone also plays a role during pregnancy to maintain the pregnancy and prevent premature lactation, but it does not stimulate milk production itself. Therefore, prolactin is specifically the key hormone that directly regulates the production of milk in the mammary glands.