Corpus Luteum

A corpus luteum is a mass of cells that forms in an ovary and is responsible for the production of the hormone progesterone during early pregnancy. The role of the corpus luteum depends on whether or not fertilization occurs. During ovulation, an egg is released from a dominant follicle. Following the release of the egg and subsequent fertilization, the follicle seals itself off and forms what is known as a corpus luteum. This mass of cells helps produce the hormone progesterone during early pregnancy. The corpus luteum will continue to produce progesterone until the fetus is producing adequate levels to sustain the pregnancy, which usually occurs between 7 and 9 weeks of pregnancy. The corpus luteum is the last active stage of an ovarian follicle’s lifecycle. Without it, early pregnancy cannot be maintained. The corpus luteum doesn’t get enough credit for the important roles in plays in pregnancy and the menstrual cycle.