Menstruation, or period, is normal vaginal bleeding that occurs as part of a woman’s monthly cycle. Every month, your body prepares for pregnancy. If no pregnancy occurs, the uterus, or womb, sheds its lining. The menstrual blood is partly blood and partly tissue from inside the uterus.
It passes out of the body through the vagina.
Periods usually start between age 11 and 14 and continue until menopause at about age 51. They usually last from three to five days. Besides bleeding from the vagina, you may have
- Abdominal or pelvic cramping pain
- Lower back pain
- Bloating and sore breasts
- Food cravings
- Mood swings and irritability
- Headache and fatigue
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.
There is a lot to learn about periods. Here are some common questions that teens have.

Most girls get their first period when they’re around 12. But getting it any time between age 10 and 15 is OK. Every girl’s body has its own schedule.
There isn’t one right age for a girl to get her period. But there are some clues that it will start soon:
- Most of the time, a girl gets her period about 2 years after her breasts start to develop.
- Another sign is vaginal discharge fluid (sort of like mucus) that a girl might see or feel on her underwear. This discharge usually begins about 6 months to a year before a girl gets her first period.
A period happens because of changes in hormones in the body. Hormones are chemical messengers. The ovaries release the female hormones estrogen and progesterone . These hormones cause the lining of the uterus (or womb) to build up. The built-up lining is ready for a fertilized egg to attach to and start developing. If there is no fertilized egg, the lining breaks down and bleeds. Then the same process happens all over again.
Vaginal bleeding normally occurs during a woman’s menstrual cycle, when she gets her period. Every woman’s period is different.
- Most women have cycles between 24 and 34 days apart. It usually lasts 4 to 7 days in most cases.
- Young girls may get their periods anywhere from 21 to 45 days or more apart.
- Women in their 40s will often notice their period occurring less often.
Many women have abnormal bleeding between their periods at some point in their lives. Abnormal bleeding occurs when you have:
- Heavier bleeding than usual
- Bleeding for more days than normal (menorrhagia)
- Spotting or bleeding between periods
- Bleeding after sex
- Bleeding after menopause
- Bleeding while pregnant
- Bleeding before age 9
- Menstrual cycles longer than 35 days or shorter than 21 days
- No period for 3 to 6 months (amenorrhea