How do the female sex organs work?

The external female sex organs include:

• Mons pubis (pubic mound)
• Outer labia (labia majora)
• Inner labia (labia minora)
• Clitoris

All of the parts of the external sex organs visible from the outside are called the vulva. Each vulva looks a little different, for instance the size and shape of the labia majora and the labia minora.

The mons pubis and the labia majora are cushioned with fat tissue and may be covered with (pubic) hair starting at puberty. These organs surround the labia minora, which are less cushioned and hairless. The opening of the vagina is between the labia minora. The skin and mucous membranes in this area have a lot of nerves and are very sensitive. As a result, touching and rubbing can cause sexual arousal that may lead to orgasm.

The clitoris is the main female organ for experiencing sexual pleasure. It consists of the head of the clitoris with a foreskin (clitoral hood), as well as the shaft and two “legs” with erectile structures (corpora cavernosa) that are positioned to the left and right of the urethra. The main part of the clitoris is located inside the body. Only the clitoral glans is visible from outside of the body, and also part of the clitoral body during sexual arousal.

The corpora cavernosa of the clitoris and of the vaginal vestibule are made of a sponge-like tissue. During sexual arousal, blood builds up in the corpora cavernosa until they are full and firm. This also causes the head and shaft of the clitoris to swell and stiffen. During an orgasm, the muscles beneath contract (tense) rhythmically.

As soon as a woman is sexually aroused, the small Bartholin’s glands at the opening of the vagina release a fluid. The vagina becomes moist, making it easier for the penis to enter during sex. There may be other small glands near the urethra (Skene's glands). They have openings in the vaginal vestibule or near the opening of the urethra and also release a secretion during sexual arousal. The Bartholin's and Skene's glands are inside of the mucous membrane and not visible from outside the body, but they are still considered part of the external female sex organs.

The jobs of the internal female sex organs are to enable pregnancy and childbirth. The internal sex organs include:

• Vagina
• Womb (uterus)
• Cervix
• Two ovaries
• Two fallopian tubes

The vagina connects the internal and external sex organs. It is an elastic tube of muscle tissue about ten centimeters long that is able to stretch a lot, for example while giving birth. It is lined with a mucous membrane containing natural vaginal flora. The flora are mostly lactic acid bacteria. They prevent germs from entering the vagina and reaching the womb, for example.

At the opening of the vagina the mucous membrane creates a fold that can make the opening a bit smaller called the hymen. The hymen can be ring-shaped and have a round hole in the middle. But it may also be crescent-shaped or have multiple small openings.

The hymen does make the vagina narrower more or less, but it is still possible for the blood of the monthly period to flow through it. Depending on the shape of the hymen, it can be torn by inserting a penis or sex toy. That could cause it to bleed, but it doesn't have to. After that, the hymen shrinks to down to a smaller size at the opening of the vagina, Some women and girls are born with a hymen that has a larger opening. So it is not possible to tell by the hymen whether a girl or woman has already had sex.

The womb (uterus) is roughly pear-shaped, and held in place in the pelvis by ligaments and muscles. The two fallopian tubes enter the upper, rounded end of the womb on the right and the left. The lower part of the womb is somewhat narrower, resembling the neck of a bottle. The lower end pushes slightly into the vagina. On the infertile days of the menstrual cycle, the opening of the cervix is closed by thick mucus.

The inside of the womb is lined with special membranes called the endometrium. In each menstrual cycle, female sex stimulate the endometrium to grow into a thick layer with higher blood flow so it is prepared for a fertilized egg: The egg can then become implanted in the lining of the womb and grow into an embryo. If fertilization doesn't take place, the thick membrane tissue which has built up is shed and leaves the woman's body during her period. If a fertilized egg becomes implanted, then a pregnancy begins. The lining is then not shed and there is no menstruation. The womb expands as the child grows.

The two ovaries are located on the right and left sides of the abdomen, and contain the eggs. These eggs can be fertilized by male sperm. The ovaries also produce important female sex such as estrogen and progesterone, which – among other things – regulate the menstrual cycle.

The fallopian tubes connect the ovaries to the uterus: During ovulation one of the two ovaries releases a mature egg cell into the opening of the fallopian tube, which is attached to the ovary like a funnel and can receive the egg cell. The egg cell moves along the fallopian tube and into the womb. The egg cell can already be reached by a sperm cell and fertilized while it is still in the fallopian tube.

The female and male sex organs develop in an embryo from the more basic structures during the first few months. Genes and hormones determine how they grow. The gonads then develop either into ovaries or testicles. Another tissue then forms the clitoris or the penis, which explains their similar structure. Sometimes the sex organs develop in a way that is neither clearly male nor clearly female. This is called intersex.

In addition to the internal and external sex organs, there are also secondary sex characteristics. They do not develop until puberty.

The female secondary sex characteristics mainly include the development of breasts and pubic and underarm hair.