Which anterior pituitary hormone stimulates estrogen secretion and egg maturation in the ovaries?

• A. FSH
• B. Growth hormone
• C. LH
• D. Prolactin

Answer: (C)

The hormone primarily responsible for estrogen secretion and follicle (egg) maturation is follicle-stimulating hormone. It acts on the granulosa cells of developing ovarian follicles, promoting their growth and triggering the enzyme machinery that converts androgens to estrogen. This estrogen production accompanies follicle maturation, setting the stage for ovulation. A surge of another pituitary hormone, luteinizing hormone, is what triggers ovulation and supports the formation of the corpus luteum, but the ongoing estrogen production and follicle growth come mainly from FSH. Growth hormone and prolactin have different roles (growth/metabolism and lactation, respectively) and do not drive this follicular maturation process.