The ovary is the primary female sex organ, and each menstrual cycle generates one ovum.
Estrogen and progesterone are two steroid hormones produced by the ovary.
Estrogen:
Estrogen stimulates the growth and activities of female secondary sex organs.
It stimulates the development of developing ovarian follicles, the emergence of female secondary sex traits (e.g., the high pitch of voice, etc.), and the development of the mammary gland.
Estrogens are also involved in the regulation of female sexual behaviour.
Progesterone:
Progesterone is a hormone that helps with pregnancy.
Progesterone also increases the production of alveoli (milk-storing sac-like structures) and milk secretion in the mammary glands.