Anatomy and physiology of the female reproductive system
Last reviewed: 23.04.2024
All iLive content is medically reviewed or fact checked to ensure as much factual accuracy as possible.
We have strict sourcing guidelines and only link to reputable media sites, academic research institutions and, whenever possible, medically peer reviewed studies. Note that the numbers in parentheses ([1], [2], etc.) are clickable links to these studies.
If you feel that any of our content is inaccurate, out-of-date, or otherwise questionable, please select it and press Ctrl + Enter.
External female genital organs
These include large and small labia and clitoris, which together constitute the vulva. Lining her two folds of the skin - large labia. They consist of adipose tissue, saturated with blood vessels, and are located in the antero-posterior direction. The skin of the labia majora is covered from the outside with hair, and inside - a thin shiny skin, on which numerous ducts of glands come out. Large labia connects front and back, forming anterior and posterior commissures (spikes). Inside of them are the labia minora, which are parallel to the large and form the vestibule of the vagina. Outside they are covered with thin skin, and inside are lined with a mucous membrane. They have a pink-red color, they are joined in front of the commissure of the large lips, and in front - at the level of the clitoris. They are sufficiently richly equipped with sensitive nerve endings and participate in the attainment of voluptuous feelings.
On the eve of the vagina, the ducts of the Bartholin glands open in the thick of the labia majora. The secret of the Bartholin glands is intensively secreted at the time of sexual arousal and provides lubrication of the vagina to facilitate frictions (periodic translational movements of the penis into the vagina) during sexual intercourse.
In the thick of the labia majora are located bulbs of the cavernous bodies of the clitoris, which increase during sexual arousal. The clitoris, which is a peculiar, greatly reduced similarity of the penis, also increases in this case. It is located in front and up from the entrance to the vagina, at the junction of the labia minora. The clitoris has a lot of nerve endings and during sex it is the dominant and sometimes the only organ by which a woman experiences an orgasm.
Just below the clitoris is the opening of the urethra, and even lower - the entrance to the vagina. In women who did not live a sexual life, it is covered with a hymen, which is a thin fold of the mucosa. The hymen can have a diverse form: in the form of a ring, crescent, fringe, etc. As a rule, at the first sexual intercourse, it breaks, which can be accompanied by moderate soreness and slight bleeding. In some women, the hymen is very dense and blocks the member from entering the vagina. In such cases, sexual intercourse becomes impossible and it is necessary to resort to the help of a gynecologist who dissects it. In other cases, the hymen is so elastic and supple that it does not break at the first sexual intercourse.
Sometimes, with coarse intercourse, especially when combined with the large size of the penis, the rupture of the hymen can be accompanied by a sufficiently strong bleeding, such that the gynecologist's help is sometimes needed.
Very rarely the hymen does not have a hole at all. During puberty, when the girl starts menstruation, menstrual blood accumulates in the vagina. Gradually, the vagina is filled with blood and squeezes the urethra, making it impossible to urinate. In these cases, a gynecologist is also needed.
The area located between the posterior adhesion of the labia majora and the anus is called the perineum. The perineum consists of muscles, fasciae, vessels, nerves. During labor, the perineum plays a very important role: due to its extensibility, on the one hand, and elasticity, on the other hand, it passes the fetal head, providing an increase in the diameter of the vagina. However, with a very large fetus or with rapid delivery, the perineum does not withstand excessive stretching and may burst. Experienced obstetricians know how to prevent this situation. If all the methods for protecting the perineum are ineffective, then resort to a cut of the perineum (episiotomy or perineotomy), since the cut wound heals better and faster than the torn wound.
Internal female genital organs
These include the vagina, uterus, ovaries, uterine (fallopian) tubes. All these organs are located in a small pelvis - bone "shell", formed by the internal surfaces of the iliac, ischial, pubic bone and sacrum. This is necessary to protect both the reproductive system of a woman and the fetus developing in the uterus.
Uterus is a muscular organ consisting of smooth muscles, reminiscent of a pear shaped. The size of the uterus is on the average 7-8 cm in length and about 5 cm in width. Despite the small size, during pregnancy the uterus can increase in 7 times. Inside the uterus is hollow. The thickness of the walls, as a rule, is about 3 cm. The uterus body is the widest part of it, it is turned upward, and the narrower neck - is directed downwards and slightly forward (normal), falling into the vagina and dividing its rear wall into the posterior and anterior arches. In front of the uterus is located the bladder, and behind - the rectum.
In the cervix, there is an opening (cervical canal) that connects the vaginal cavity with the uterine cavity.
Fallopian tubes extending from the lateral surfaces of the uterine fundus on both sides - paired organ 10-12 cm long. Divisions of the fallopian tube: uterine part, isthmus and ampulla of the uterine tube. The end of the tube is called a funnel, from the edges of which numerous branches of various shapes and lengths (fimbriae) leave. Outside, the tube is covered with a connective tissue membrane, under it there is a muscular membrane; the inner layer is the mucosa, lined with a ciliated epithelium.
Ovary - paired organ, sex gland. Oval body: length up to 2.5 cm, width 1.5 cm, thickness about 1 cm. One pole is connected to the uterus by its own ligament, the second - facing the side wall of the pelvis. The free edge is open in the abdominal cavity, the opposite edge is attached to the wide ligament of the uterus. It has a brain and cortical layers. In the brain - vessels and nerves are concentrated, in the cortical - follicles ripen.
The vagina is an expandable muscle-fibrous tube about 10 cm long. The upper edge of the vagina covers the cervix, and the lower one opens on the eve of the vagina. The cervix protrudes into the vagina, a domed space forms around the neck - the anterior and posterior vaults. The wall of the vagina consists of three layers: the outer - dense connective tissue, the middle - thin muscle fibers, the inner - the mucous membrane. Some of the epithelial cells synthesize and conserve glycogen stores. Normally, the vagina is dominated by Dodderlein sticks, which process the glycogen of dying cells, forming lactic acid. This causes the maintenance of an acidic environment in the vagina (pH = 4), which has a harmful effect on other (non-acidophilic) bacteria. Additional protection against infection is carried out by numerous neutrophils and leukocytes residing in the vaginal epithelium.
The mammary glands are composed of glandular tissue: each of them contains approximately 20 separate tubuloalveolar glands, each of which has its opening on the nipple. Before the nipple, each duct has an expansion (ampulla or sinus), which is surrounded by smooth muscle fibers. In the duct walls there are contractile cells, which in response to sucking are reflexively contracted, expelling the milk contained in the ducts. The skin around the nipple is called the areola, it contains many glands like dairy, as well as sebaceous glands producing an oily liquid that lubricates and protects the nipple when sucking.