Role of the vagina in sex, reproduction, and childbirth

The vagina is a muscular tube that provides a passageway from the outside of the body to the uterus (uterus). The vagina has the ability to change in size to accommodate intercourse and provide a "birth canal" through which a baby can be born.

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The structure of the vagina.

The vagina is made up of tissues, fibers, muscles, and nerves. The external mucous tissue is covered with a layer of connective tissue that, together, produces mucus for vaginal lubrication. Beneath these is a layer of smooth muscle that can contract and expand, followed by another layer of connective tissue known as the adventitia.

The vagina is located between the vulva (external genitalia) and the cervix (a narrow, neck-shaped tube that separates the vagina from the uterus).

The general structure of the vagina is as follows:

  • The vaginal opening is between the anus and the opening of the urethra (through which urine leaves the body). The openings to the vagina and urethra are protected by the labia.
  • Just below the urethra is the opening, also called the vestibule or opening of the vagina .
  • The vaginal canal then moves up and back between the urethra in the front and the rectum in the back.
  • As the distal end of the vaginal passage, the ectocervix (the outer part of the cervix) protrudes markedly into the vaginal canal.

The length of the vagina can vary in women of childbearing age from an average of 2.5 to 3.5 inches.

With regard to lubrication, vaginal discharge can increase during sexual arousal, pregnancy, and at various stages of menstruation. During the menstrual cycle , the mucous membrane thickens and the composition of the mucus changes to facilitate fertilization.

Vagina and intercourse

During sexual arousal, the vaginal mucous membranes begin to produce more lubrication as the vagina expands in both length and width. This reduces friction and the risk of penetration injuries to the vagina.

The vagina can continue to lengthen when the woman is fully aroused as the cervix reverses and begins to retract. This can cause the uterus to rise towards the pelvis and create a so-called "swelling effect" in which the walls of the vagina stretch and contract around the penis, providing stimulation and stimulating ejaculation .

The vagina itself does not have many nerve endings, so many women cannot achieve sexual stimulation from vaginal penetration alone. On the other hand, the clitoris is rich in nerves and can work in conjunction with the vagina to achieve orgasm during intercourse.

The vagina during childbirth.

During labor, the vagina provides a passage through which the baby is born. When labor begins, a woman usually experiences vaginal discharge, contractions, ruptured membranes, and a leak or discharge of amniotic fluid from the vagina.

As labor approaches, the cervix begins to thin and soften, allowing the baby to sink into the pelvis. Then the baby begins to lose support for the cervix as contractions begin and the cervical opening (opening) begins to expand.

When the cervix is dilated more than four inches (10 centimeters), the baby will move from the uterus to the vagina. The structure of the vagina is such that it can stretch many times its normal diameter to accommodate childbirth.

After pregnancy and estrogen flow are restored to normal, the vagina will return to its approximate pre-pregnancy state in about six to eight weeks.

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