What Role Does the HPG Axis Play in the Menstrual Cycle?
The menstrual cycle is orchestrated by the HPG axis. In the follicular phase, FSH promotes the growth of ovarian follicles, which secrete estrogen. Rising estrogen levels lead to a surge in LH, triggering ovulation. In the luteal phase, the ruptured follicle forms the corpus luteum, which secretes progesterone to prepare the endometrium for potential pregnancy. If pregnancy does not occur, the corpus luteum degenerates, leading to a drop in progesterone and estrogen, resulting in menstruation.
