How do FSH and LH control ovulation in mammals?

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In mammals, the pituitary gland regulates ovulation through the coordinated action of two gonadotropic hormones: follicle-stimulating hormone (FSH) and luteinizing hormone (LH).12

  • Follicular Phase: At the start of the cycle, FSH promotes the growth and maturation of ovarian follicles, which contain the developing eggs. As these follicles mature, they secrete increasing amounts of [estrogen].3245
  • Ovulation: The rising levels of estrogen provide feedback to the pituitary gland, which triggers a surge in LH secretion (and, to a lesser extent, FSH). This preovulatory surge of LH is essential for the rupture of the mature Graafian follicle, resulting in the release of the egg—the process of ovulation.542
  • Luteal Phase: Following ovulation, LH stimulates the empty follicle to transform into the corpus luteum, which then produces progesterone to support potential pregnancy.124

While these hormones act spontaneously in many mammals, some species (such as cats and rabbits) require the stimulus of copulation to trigger the release of the ovulatory hormone.54