Reproductive System

External female genitals include the mons veneris, labia majora, labia minora, clitoris, and vestibule. They differ in size and color from female to female, but their location and function are consistent. The mons is a pad of fatty tissue filled with many nerve endings which becomes covered with pubic hair in puberty. The labia majora are two folds of skin which protect the opening to the urethra and internal genitals. Pubic hair grows on their outer surface in puberty. These fat padded folds of skin contain sweat glands, nerve endings, and numerous blood vessels. Inside these outer skin folds are the labia minora which are hairless. The labia minora form a spongy covering for the vaginal entrance. These smaller skin folds meet at the top of the genitals to form the clitoral hood. The hood houses the clitoris, a very sensitive organ which has a spongy shaft and a nerve-rich glans (tip). Between the labia minora and the vagina is the area called the vestibule. Within the vestibule are the two Bartholin's glands which lubricate the vagina.

Sexual arousal in females parallels the arousal stages in males. Female sexual arousal is not required to reproduce, but it does facilitate reproduction. In the excitement phase, blood flow to the vagina increases which, in turn, pushes fluid into the vaginal canal. This lubricating process is called transudation and allows for comfortable penile insertion. During this phase, blood infiltrates the spongy clitoris and labia, and the cervix and uterus are lifted up away from the vagina. Respiration, heart rate, and blood pressure increase.

During the plateau stage, the vagina expands, forming a pocket near the cervix which is an ideal deposit site for sperm; this is called "tenting." The increased sensitivity of the clitoris causes it to retract in the clitoral hood, and breasts sometimes become flushed. In the orgasmic phase, the vaginal opening contracts rhythmically for about 15 seconds. Unlike the lengthy refractory period which males experience in the resolution stage, females are more likely to be multi-orgasmic and capable of more closely spaced orgasms. In the resolution stage, genital blood flow returns to normal. Respiration, heart rate, and blood pressure also return to normal. Within 72 hours of sexual intercourse reproduction will either have successfully begun or not succeeded.