What does a human vagina look like

Internal genitalia of the woman

Womb (uterus)

The uterus is roughly the shape and size of an upside-down pear and is approx. 7 - 9 cm long at sexual maturity. Inside is the uterine cavity (Cavum uteri). The upper two thirds of the uterus is called the body of the uterus (corpus uteri), the lower, narrow third is called the cervix (cervix). In adult women, the uterus weighs around 80 and 120 grams, and during pregnancy it increases to a good one kilogram.

In simple terms, the uterine wall consists of three layers:

  • Perimetrium: outer covering with peritoneum,
  • Myometrium: thick middle layer of smooth muscle cells,
  • Endometrium: the internal mucous membrane that lines the uterine cavity.

Cervix

The cervix, the outer area of ​​the uterus, is the connection between the vagina and the uterus. The cervix is ​​divided into the part that protrudes into the vagina (portio vaginalis uteri, external cervix) and the mucus-forming cervical canal that opens into the uterine cavity. At the transition point between the external cervix and the cervical canal, tissue shifts occur - depending on the status of the sex hormones and age: the vaginal skin can migrate into the cervical canal, and vice versa, the mucus-forming cylindrical epithelium of the cervical canal also grows into the cervix. The portio, the external cervix, is covered with a special layer of cells, the so-called uncornified squamous epithelium. Due to the interplay of the 2 different types of tissue, this area is susceptible to infections, including viral infections (human papilloma viruses), which can promote the development of cancer. This is usually the area where cervical cancer (cervical cancer) can develop. To function as a barrier between the vagina and the inner part of the uterus, the cervix secretes mucus. The consistency of the mucus changes during the cycle. On infertile days it is viscous and closes the cervix so that neither bacteria nor sperm can penetrate. On the other hand, on fertile days, i.e. a few days before and after ovulation, the mucus is thin. Then sperm can rise up the cervix and go into the uterus to fertilize an egg.

Uterine body (corpus uteri)

The body of the uterus houses the uterine cavity (uterine cavity) in which the pregnancy is carried out. The fallopian tubes on both sides, which are responsible for transporting the egg, open into the uterine cavity at the upper right and left angles.

The mucous membrane of the uterine cavity (endometrium) is regularly built up and broken down by the influence of hormones. If an egg cell is not fertilized within a cycle, the built-up endometrium is rejected again by hormonal control and excreted together with the blood of the torn mucous membrane vessels as menstruation.
If the zygote settles in the uterine lining after fertilization, a fertilized egg cell is called, the endometrium continues to grow in order to ensure the supply of the embryo. The myometrium is also able to stretch and grow significantly during pregnancy. It adapts to the increasing space requirements of the child and the placenta (placenta = prenatal care system) by changing its shape. The internal volume of the uterus increases to about 5 liters. During pregnancy and childbirth, the muscles of the myometrium contract and develop the driving force called contractions. Different types of labor occur depending on the stage of pregnancy and birth.

If the uterus is removed (hysterectomy), there will be no menstrual period and pregnancy to term is no longer possible. However, the female hormones of the ovary are released into the blood and are therefore still available to the body in the usual way.