Why do girls bleed during their periods?

Menstrual period is also called "menstrual holiday", "menstrual holiday" or "old friend". A healthy woman has vaginal bleeding (actually uterine bleeding) once a month for 3 to 7 days. This regular vaginal bleeding is menstruation.

Menstruation is a unique physiological phenomenon of women. It is also an important sign of the development and perfection of women's reproductive organs. It is the main manifestation of the function of the uterus and ovaries, indicating their natural ability to conceive.

1. Why does menstruation occur?

All the eggs in a woman's life are transformed during the fetal period and cannot be saved at birth.

When a baby girl is born, there are 700,000 to 2 million initial eggs in the uterus and ovaries, but not all eggs can grow and develop fully.

During the growth and development of women, most of the initial eggs die, and only a very small number of eggs can survive to puberty.

Under the control of the hypothalamus-pituitary gland, the anterior pituitary gland metabolizes a certain type of growth hormone (follicle-stimulating hormone) to promote the development of the uterus and produce and metabolize female hormones.

Under the action of estrogen, the uterine wall begins to multiply, and the secretion of follicle-stimulating hormone and progesterone peaks 1 to 2 days before ovulation, which promotes the development of the uterus and stimulates the ovaries to release eggs.

Then estrogen levels begin to drop, and the egg matures and ovulates.

After ovulation, under the action of estrogen, the uterine wall becomes more puffy, fully preparing for the sperm and egg to combine and settle down.

If the discharged egg cell can meet the male sperm, the sperm and egg will combine and grow into a test tube embryo and fetus again until the pregnant woman gives birth;

If the egg is not pregnant, the corpus luteum (a new corpus luteum is produced in each menstrual cycle, and the basic function of progesterone is to produce and metabolize progesterone to prepare for uterine pregnancy) begins to shrink, and the secretion of estrogen and estrogen will also decrease rapidly. The uterine wall suddenly loses the support of these two hormones, and the blood vessels will contract, causing the uterine wall to shrink, necrotize and fall off, causing bleeding.

The discharge of blood and shed uterine wall from the vagina is what we commonly call "menstruation".

2. What are the menstrual cycles and menstrual periods like?

From a physiological point of view, menstruation is the result of failed pregnancy. Even if there are repeated failures, the uterine wall is always on guard and fully prepared for every possible pregnancy.

The eggs in the ovaries also begin to grow and develop, entering the next menstrual cycle. This cycle repeats itself over and over again, gradually becoming a regularity.

A normal menstrual period has a certain regularity. The first day of bleeding is the beginning of the menstrual cycle, and the interval between the first days of two menstruations is called "one menstrual cycle".

The average menstrual cycle is 28 days, but if it is 7 days earlier or 7 days later, as long as it is always regular, it can basically be considered normal.

The duration of each menstrual period is called the "menstrual period", which usually lasts 3 to 7 days.

Menstrual volume refers to the total amount of blood loss during one menstrual period. Normal menstrual volume is 20-60mL, and exceeding 80mL is considered excessive menstrual volume.

Menstrual blood is dark red. In addition to blood, it also contains fragments of uterine wall, cervical mucus and fallen squamous epithelial cells in the vagina.

Because menstrual blood contains prostacyclin and substances from the uterine wall that promote blood non-coagulation (free fatty acid lysozyme), menstrual blood is generally not easy to coagulate.

But if the menstrual period is too heavy, blood clots will also occur.

3. Is menstrual blood dirty?

In fact, menstrual blood itself is not clean, but it is a good nutrient for bacteria and other microorganisms. Therefore, you need to pay attention to hygiene during your menstrual period to avoid reproductive system infections.

4. What are the symptoms of menstrual period?

Generally speaking, there are no special symptoms during the menstrual period, but due to pelvic congestion and the effects of some special substances (such as prostacyclin) during the menstrual period, some women will experience discomfort in the lower abdomen and lumbosacral region or uterine contraction pain, and may also experience digestive tract disorders such as diarrhea or constipation.

A very small number of women may also experience headaches and mild central nervous system instability symptoms, such as irritability, anger, and sadness.

If you experience unbearable lower abdominal pain during your menstrual period or before and after your menstrual period, you need to be alert to whether there are certain diseases. The most common one is a disease called "endometriosis and adenomyosis".

5. What should you pay special attention to during your menstrual period?

Menstruation is a normal physiological phenomenon for women, but women who have just entered puberty may feel hesitant and afraid.

As parents, especially mothers, they should tell their children the origins of this physiological phenomenon when appropriate.

In addition to not doing heavy physical work and intense outdoor activities during menstruation, you should also pay attention to menstrual hygiene.

There is no need to swim or take a sitz bath during menstruation. During menstruation, you should not eat too much or eat hot and cold food, otherwise it will cause digestive discomfort and even aggravate menstrual pain.