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How does luteinizing hormone trigger ovulation?

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Detailed cross-sectional illustration of a human ovary showing the stages of follicle development, ovulation, and corpus luteum formation, with labeled structures including primordial, primary, secondary, and mature follicles, a ruptured follicle releasing an ovum, and corpus luteum and albicans. An inset at the bottom shows the ovary's location in the female reproductive system. — ovary The steps of ovulation, beginning with a dormant primordial follicle that grows and matures and is eventually released from the ovary into the fallopian tube.

Luteinizing hormone (LH) is a gonadotropic hormone produced by the pituitary gland that plays a critical role in the regulation of the ovary.12

During the menstrual cycle, maturing follicles secrete increasing amounts of estradiol. This rise in estradiol, alongside small amounts of progesterone, triggers a transient, significant surge in LH secretion from the pituitary gland. This LH surge is the primary mechanism that causes the mature Graafian follicle to rupture, resulting in ovulation—the release of the mature egg from the ovary.34

Following ovulation, LH continues to function by promoting the transformation of the ruptured follicle into the corpus luteum, an endocrine gland that secretes progesterone to support potential pregnancy.124