The two ovaries, which are about the size and shape of almonds, are at the ends of the fallopian tubes, one on each side of the uterus. They are connected to the pelvic wall and the uterus by ligaments. The ovaries are endocrine glands that produce three classes of sex hormones. The estrogens, as mentioned in Chapter 5, influence development of female physical sex characteristics and help regulate the menstrual cycle. The progestational compounds also help regulate the menstrual cycle and promote maturity of the uterine lining in preparation for pregnancy. Around the onset of puberty the female sex hormones play a critical role in initiating maturation of the uterus, ovaries, and vagina and in developing the secondary sex characteristics, such as pubic hair and breasts.
The ovaries contain about 1 million immature ova at birth and between 400,000 and 500,000 at menarche (Federman, 2006). During the years between puberty and menopause, one or the other ovary typically releases an egg during each cycle. Only 400 ova are destined for full maturation during a woman’s reproductive years (Macklon & Fauser, 1999). Ovulation (ahv-yoo-LAY-shun), or egg maturation and release, occurs as the result of the complex chain of events we know as the menstrual cycle, discussed in the next section.
Female Sexual Anatomy and Physiology