Definition: A hormone secreted by the corpus luteum (a mass of cells that forms on the ovary at the place where an egg released) after ovulation.
Progesterone is meant to prepare the uterus for pregnancy, among other things. If pregnancy occurs, progesterone production is eventually provided by the placenta. If pregnancy doesn’t occur, the corpus luteum disintegrates within 12 to 16 days and stops producing progesterone, which then leads to menstruation.
