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A period is a release of blood from a girl's uterus, out through her vagina. It is a sign that she is getting close to the end of puberty. It also means that she can get pregnant if she has sex.
There is a lot to learn about periods. Here are answers to some common questions.
Most girls get their first period when they're around 12. But sometimes it comes a few years earlier or later. Every girl's body has its own schedule.
There isn't one right age for a girl to get her period. But signs to watch for include:
A period happens because of changes in hormones in the body. Hormones are chemical messengers. The ovaries release the female hormones estrogen and progesterone , which cause the lining of the uterus (or womb) to build up. The built-up lining is ready for a fertilized egg (an egg that has joined with a sperm) to attach to and develop into a baby. If there is no fertilized egg, the lining breaks down and bleeds. Then the same process happens all over again.
It usually takes about a month for the lining to build up, then break down. That is why most females get their periods around once a month.
Ovulation (pronounced: ov-yoo-LAY-shun) is the release of an egg from the ovaries. The same hormones that cause the uterus lining to build up also cause an egg to leave one of the ovaries. The egg travels through a thin tube called a fallopian tube to the uterus.
If the egg is fertilized by a sperm cell, it attaches to the wall of the uterus, where over time it develops into a baby. If the egg is not fertilized, the uterus lining breaks down and bleeds, causing a period.
For the first few years after a girl starts her period, it might not come regularly. This is normal at first. By about 2–3 years after her first period, a girl's periods should be coming around once every 4–5 weeks.
Yes, a girl can get pregnant as soon as her period starts. A girl can even get pregnant right before her very first period because her hormones might already be active. The hormones may have led to ovulation and the building of the uterine wall. If so and the girl has sex, she can get pregnant, even though she has never had a period.
Periods usually last about 5 days. But a period can be shorter or last longer.
Periods usually happen about once every 4–5 weeks. But some girls get their periods a little less or more often.
You have many choices about how to deal with period blood. You may need to experiment a bit to find which works best for you. Some girls use only one method and others switch between different methods.
It may look like a lot of blood, but a girl usually only loses a few tablespoons of blood during the whole period. Most girls need to change their pad, tampon, or menstrual cup about 3‒6 times a day.
When women reach menopause (around age 45‒55), their periods will permanently stop. Periods also stop during pregnancy.
PMS (premenstrual syndrome) is when emotional and physical symptoms happen before or during a girl's period. These can include moodiness, sadness, anxiety, bloating, and acne. The symptoms go away after the first few days of a period.
Many girls have cramps with their period, especially in the first few days. If cramps bother you, you can try:
Most girls don't have any problems with their periods. But call your doctor if you:
Periods are a natural, healthy part of life. They shouldn't get in the way of exercising, having fun, and enjoying life. If you have questions about periods, ask your doctor, a parent, health teacher, school nurse, or older sister.
This video shows what happens during the menstrual cycle – and why.
Note: All information is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.
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