A girl's periods can cause some uncomfortable symptoms. It may look like a lot of blood, but a girl usually only loses a few tablespoons of blood during the whole period. It usually takes about a month for the lining to build up, then break down. If you have questions about periods, ask your doctor, a parent, health teacher, school nurse, or older sister. This is because a girl's hormones might already be active. Hormones are chemical messengers.
But there are some clues that it will start soon:.
All About Periods
But there are some clues that it will start soon:. You may need to experiment a bit to find which works best for you. More on this topic for: But by about 2 years after periods start, they should be on a regular cycle. PMS usually goes away 2 to 3 days after the period begins. But some problems need care from your doctor. Pelvic Exams Vaginal Discharge: