What is the hymen?

What does the hymen refer to? The hymen is a membrane that protects the female vagina. It plays a very important role. Before a woman has sexual life, it can prevent foreign bacteria from invading the vagina and acts as a natural barrier. The hymen is located at the external opening of the vagina, about one centimeter thick. When a woman has her period, fluid will flow out through this small hole. The hymen will rupture and bleed after the first night, but it is not absolute.

The hymen covers the vagina near the external opening, is about 1 to 2 mm thick, and has a small hole in the middle, called the "hymen hole", with a diameter of about 1 cm. It is usually round, oval or serrated; some are crescent-shaped, with the hole on one side; some are septum-shaped, with two small holes arranged vertically or horizontally; some have many scattered small holes, like a sieve.

During menstruation, menstrual blood is discharged from the body through this small hole. If there are no small holes in the membrane, the monthly menstrual blood will be blocked, accumulate in the vagina, and expand upward to the uterine cavity and fallopian tubes, and even flow into the abdominal cavity, causing damage to the fallopian tubes, intestinal adhesions, and abdominal infection. This is medically called "hymen occlusion" and gynecological surgery must be performed.

Before puberty, because the ovaries secrete less estrogen, the vaginal mucosa is thin, with fewer wrinkles, low acidity and weak resistance, the hymen has the function of preventing bacteria from invading the vagina. After puberty, with the development of the ovaries, the amount of estrogen in the body increases, the resistance of the vagina increases, and the hymen loses its function.

First night:

During the first sexual intercourse, the hymen is broken and a tear is formed, causing bleeding.

Because the hymen has different shapes, the degree of rupture can vary greatly. The septate hymen with two holes will bleed more and be accompanied by more severe pain. The labial hymen bleeds very little and is almost painless. A thick and elastic umbrella-shaped hymen may not rupture at all!

According to a survey of American gynecologists, about 30% of women do not bleed during their first sexual intercourse. This 30% includes the more elastic umbrella-shaped hymen, which may rupture after multiple sexual intercourses or after a particularly wild sexual journey, but may not necessarily cause bleeding. It also includes the porous sieve-shaped hymen, which is extremely easy to rupture and may have ruptured for various reasons before the first sexual intercourse.

After giving birth:

As the fetus is delivered vaginally, the hymen is further damaged. Sometimes only a few residual protrusions are left, called hymenal scars. This change does not occur with a caesarean section delivery.