How old are girls when they have their first period?

A girl's menarche is actually a sign of entering puberty. Generally, the time of menarche is between 12 and 18 years old, but there will be certain fluctuations depending on the individual's physical constitution. Therefore, for young girls, it is still necessary to know more about these physiological health common sense so that you can know your own physical health status. Now let's learn about some common knowledge about girls' menarche.

Women's menarche usually occurs during puberty, usually between the ages of 12 and 18. Very rarely, menstruation occurs before the age of 10 or later than the age of 18.

Menstruation is related to cyclical changes in the ovaries and uterine membrane. Starting from puberty, the egg cells in the ovaries gradually develop, mature and are released. At the same time, the ovaries secrete estrogen and progesterone, which promote the thickening of the endometrium and the proliferation of blood vessels, creating conditions for the fertilized egg to develop in the uterus. If the discharged egg is not fertilized, the secretion of estrogen and progesterone in the ovaries will decrease rapidly, causing necrosis and shedding of endometrial tissue and rupture and bleeding of blood vessels. The shed endometrial fragments along with blood are discharged from the vagina, which is menstruation.

The onset of menstruation is an important sign of a girl's entry into puberty. Most girls begin to menstruate when they are 12 to 14 years old. The first menstruation is called menarche. The menstrual cycle is generally 28 to 30 days. Each menstrual period is 3 to 7 days, and the amount of bleeding is 30 to 60 ml. However, some girls have irregular menstruation, sometimes it comes every 2-3 days, sometimes it comes twice a month, and some even have no period for several months. Some have too much bleeding, and some have too little bleeding. What is the reason for irregular menstruation during adolescence?

It turns out that the girl is in the period of sexual maturity, and the function of the hypothalamus-pituitary-ovarian axis has not yet fully matured. She does not ovulate when she starts menstruating, but only produces estrogen, which causes the endometrium to proliferate. However, the estrogen level is very low, which stops the endometrium from proliferating and causes it to shed and bleed. Therefore, some girls have to wait several months after their menstruation, and sometimes they have irregular bleeding, and sometimes they have continuous bleeding after a short period of amenorrhea. This is the reason for the girls' menstrual disorders. After a period of adjustment, the ovaries mature and can ovulate regularly, and then a normal menstrual cycle can be established.

In addition, mood swings, excessive exercise, work and study stress, and changes in environment and climate can all affect the menstrual cycle. Every young girl has her own menstrual cycle. Some girls have their periods once every two months or even once every six months. This is normal and there is no need to worry about it.

When women have their first menstruation, they should pay more attention to their menstrual hygiene, add more nutrition to their diet, keep their private parts dry to avoid bacterial growth, and not blindly take medication when some abnormal conditions occur, as this is likely to have more adverse effects. I also hope that parents and friends can pay more attention to adolescent girls.