Follicle-stimulating hormone is a gonadotrophin released by the anterior pituitary in response to pulsatile gonadotrophin-releasing hormone stimulation.

It is responsible in females for the early growth of ovarian follicles

In males, together with testosterone (1), it stimulates Sertoli cells to release the hormone inhibin and induces sperm production. Inhibin and testosterone reduce gonadotrophin-releasing hormone (and hence gonadotrophin) secretion via negative feedback.