Question

During pregnancy, which hormone prevents milk ejection while supporting lobule development for future lactation?

Options

• Oxytocin from the posterior pituitary

• Prolactin from the anterior pituitary

• Progesterone from the corpus luteum

• Oestrogen from the ovary

Answer 1

Progesterone, secreted by the corpus luteum during pregnancy, has a dual role: it promotes lobule development in preparation for lactation while simultaneously suppressing premature milk ejection. This prevents lactation from occurring prematurely before childbirth, ensuring milk production is initiated only after parturition when the infant is ready to feed.