The Female Reproductive System
Most of the important reproductive parts of the woman are internally located, but the parts you play with are primarily located on the outside of the body. All of the external structures are referred to as the vulva. No, John, it is not the name of a car! The internal structures consist of the vagina, uterus, fallopian tubes, and ovaries.
As we mentioned, the external genitals of the woman are known as the vulva and include the mons pubis, labia, clitoris, opening of the urethra, and vaginal entrance. On the sides of the urinary and sexual openings are the labia majora (large lips). These two large folds of skin extend down from the mons pubis to the front edge of the perineum (skin between the vagina and anus, also known as ‘taint.’)
On either side of the labia majora and closer to the vaginal entrance are the two labia minora (small lips). These small folds of skin extend down and back from the clitoris for approximately one and one-half inches.
The clitoris is an erectile structure that is similar to the male penis. The clitoris consists of two corpus cavernosa enclosed in a dense layer of fibrous tissue. The body of the clitoris is concealed beneath the labia within the clitoral hood. The glans clitoris is a small round structure that is made up of highly sensitive erectile tissue. During arousal, the clitoris becomes erect and the head of clitoris protrudes from under the hood.
Between the clitoris and vaginal entrance is a smooth, triangular-shaped structure called the vestibule. It is surrounded on each side by the labia minora. The vestibule contains the opening of the urethra. Unlike the urethra of the man that passes urine and sexual fluids, the woman’s urethra passes only urine. The woman’s bladder can still empty during sexual excitement since there is no blockage as there is in men during sexual arousal. The vestibule also contains ducts from the Bartholin’s glands. Bartholin’s glands, located on each side of the vagina, have been compared to the Cowper’s glands in the man. These glands secrete mucus at the vaginal entrance that contributes to vaginal lubrication.
The internal structures consist of the vagina, uterus, fallopian tubes, and ovaries. The vagina is a tube-shaped structure located in the pelvic cavity, extending upward and backward from the vulva to the neck of the uterus or cervix. It is located between the urinary bladder and rectum. The vagina is a highly-vascular structure consisting of a layer of mucus tissue, a layer of erectile tissue, and a muscular coat. The mucus tissue, while containing no glands, does secrete mucus that aids in lubrication. The vaginal walls are normally in contact with each other; however, during sexual stimulation and intercourse, the walls expand to accommodate the penis. Further, during childbirth and the descent of the fetus, the vaginal walls can expand up to a diameter of 15 cm.
The uterus is a pear-shaped organ located behind and above the urinary bladder. It consists of two parts: the body of the uterus and the cervix. The body of the uterus extends from the top called the fundus, located at the brim of the pelvis, and gradually narrows to form the neck or cervix.
On each side of the uterus, near the top, are the fallopian tubes. The fallopian tubes extend outward to the sides for approximately 10 cm and end in finger-like projections called fimbria. During ovulation, the fimbria fill with blood and begin swaying back and forth along the surface of the ovary. This motion, along with muscular contractions of the fallopian tube, pulls the egg into the tube, toward the uterus. The lining of the fallopian tubes consists of mucus tissue lined with hair-like fibers called cilia. The cilia, along with muscular contractions, propel the ovum toward the body of the uterus.
The ovaries are located on each side of the uterus at the end of each fallopian tube. The ovaries have two functions: the production of ova or eggs and the secretion of sex hormones. The ovaries are highly vascular and consist of an outer coating and an inner soft tissue consisting of numerous cells. When the woman ovulates, the egg-containing follicle ruptures releasing the egg. Occasionally women will complain of mid-cycle, one-sided, lower abdominal cramping associated with the rupture of the follicle.
Sexual Arousal, Lubrication, and Orgasm
Similar to the male, arousal in women originates with local stimulation of the genitals that is perceived as being sexual in nature. Stimulation from the spinal cord causes the arteries to dilate and veins to constrict in the erectile tissues in the vulva. Stimulation of the Bartholin’s glands causes the glands to secrete mucus to aid in lubrication. This stimulation of the erectile tissues in the vagina also causes an increased mucus production and release of fluids from areas between the cells of the vagina.
When stimulation is significant and is accompanied by sufficient psychic signals, the female orgasm or climax will begin. The female orgasm is controlled by the nervous system originating in the spinal cord, similar to the muscular contractions during ejaculation in the male.