Menstruation is part of the process your body goes through to get ready for the possibility of pregnancy each month. Each month, an ovary releases an egg. The egg travels through a tube called the fallopian tube into the uterus. Hormones make the lining of the uterus thicker to get ready for a baby in case the egg is fertilized by sperm. If a man's sperm does not fertilize the egg, the uterus sheds the lining it prepared for a baby. When the uterus sheds its lining, blood flows out of your vagina. This is called menstrual flow, or your period.
A menstrual cycle is the time from the day your period starts to the time your next period starts. Your menstrual cycle may vary from 21 to 35 days long. Most periods last 3 to 5 days, but anywhere from 2 to 7 days is normal. Menstrual cycles may start around the same date every month or they may be irregular.
A late period means that it hasn’t started 5 or more days after the day you expected it to start. A missed period means that you have had no menstrual flow for 45 days after the start of your last period.
During the first couple of years of menstruation many teens have irregular periods. During this time your body is still developing and your ovaries may not release an egg every month. As a result, your cycles may be irregular. You may have a period every 2 weeks or once every 3 months. Most girls' menstrual cycles become regular as their hormone levels mature. If you have not had a period for 45 to 90 days, contact your healthcare provider.
Other causes of a late or missed period are:
If your period is late and you have had sex even once in the past several months, see your healthcare provider for a pregnancy test. Most home test kits are accurate, but may give incorrect or unclear results. It is important to find out early if you are pregnant. Starting prenatal care right away helps you have a healthy baby.
Problems with the thyroid gland, pituitary gland, adrenal glands, or ovaries are less common causes of irregular periods.
Your healthcare provider will ask about your symptoms and medical history and examine you, including a pelvic exam. Tests may include:
You may have other tests or scans to check for other possible causes of your symptoms.
The treatment depends on the cause. Examples of possible treatments are:
In some cases, you may not need treatment.
Follow the full course of treatment prescribed by your healthcare provider. In addition:
Ask your provider:
Make sure you know when you should come back for a checkup. Keep all appointments for provider visits or tests.