Which structure secretes progesterone and estrogen?

The corpus luteum is the structure responsible for secreting both progesterone and estrogen following ovulation. After a mature ovarian follicle releases an egg, the remaining structure transforms into the corpus luteum. This temporary endocrine gland plays a crucial role in regulating the menstrual cycle and maintaining early pregnancy.

Progesterone is vital for preparing the endometrium for potential implantation of a fertilized egg, while estrogen contributes to several reproductive processes, including the regulation of the menstrual cycle and supporting pregnancy. If pregnancy does not occur, the corpus luteum degenerates, leading to a drop in hormone levels, ultimately resulting in menstruation.

Other structures mentioned, such as the follicle, mainly produce estrogen before ovulation, and while the ovaries as a whole are involved in hormone production, it is specifically the corpus luteum that is critical for the secretion of these hormones during the luteal phase of the menstrual cycle. The adrenal gland, while capable of producing sex hormones, is not the primary source for progesterone and estrogen in relation to the menstrual cycle or early pregnancy.