Which hormone is known to spike just before ovulation?

The hormone that is known to spike just before ovulation is luteinizing hormone (LH). During the menstrual cycle, a surge in LH is critical for the process of ovulation, which occurs approximately 24 to 36 hours after the LH peak. This surge is triggered by rising levels of estrogen that are produced by developing follicles in the ovary, signaling the hypothalamus and pituitary gland to release LH.

The increase in LH levels leads to the final maturation of the ovarian follicle and induces the ovary to release an egg. This physiological response is an essential part of the reproductive cycle and is fundamental for fertility.

In contrast, estrogen levels increase leading up to ovulation, but they do not specifically spike at the moment of ovulation like LH does. Progesterone is primarily involved after ovulation, in preparing the uterine lining for potential implantation of a fertilized egg. Follicle-stimulating hormone (FSH) plays a role in the early stages of follicle development but does not have the marked surge right before ovulation like LH does. Thus, the distinct peak in luteinizing hormone is a key marker of the ovulation phase in the menstrual cycle.