Missed Periods

You thought it was that time of the month, but your period didn’t arrive. Don't panic! During the teen years, your period may not always arrive on time or regularly. In fact, it can take up to two years from the time you start menstruating for your body to develop a regular cycle.

Although it’s important to remember that pregnancy can be a possibility if you’re sexually active (see a healthcare provider if you think you may be pregnant), here are other reasons that you might miss a period.

Excessive Exercise

High school sports are a great source of exercise, but you may see a change in your menstrual cycle if you’re training hard.

You may experience less bleeding, shorter or less frequent periods, or your period may stop completely. This is how your body conserves energy during times of strenuous activity.

Usually periods return to normal several months after you’ve stopped strenuous sports participation. Don’t be concerned if periods are infrequent, such as several times per year rather than once per month.

However, if your periods have stopped completely for more than six months, go see your doctor to rule out any medical cause. Absence of periods for more than one year can cause loss of bone density and increase the risk of stress fractures during sports. It can also increase the risk of osteoporosis later in life.

Birth Control

Although birth control pills are often prescribed to regulate a women’s period, they can also cause you to miss your period. If you’re using a hormonal method of birth control such as Depo-Provera or mini-pills, you may miss or fail to have a period.

It’s not abnormal to miss your period while on birth control. In fact, you may not experience any bleeding during the placebo week (the week that you take inactive pills) until you’ve stopped taking birth control completely.

However, if you’re concerned you may be pregnant, take a urine pregnancy test or speak to a healthcare provider.

Amenorrhea

If you don’t get your period, a medical condition called amenorrhea could be to blame. Some women who haven’t started their period by age 16 may have amenorrhea-primary. Amenorrhea-primary has several causes, so if you’re concerned, see your healthcare provider.

Amenorrhea-secondary is a condition in which menstruation begins at a typical age but later stops for six or more months. If you haven’t had a period in more than six months, see your healthcare provider.

Stress

While some stress is normal for teenagers, an excessive amount of stress can be harmful to your health. If you’re under a lot of emotional stress, either from school or your family, it can affect your period.

Eating Disorders

Each year, millions of people in the United States are affected by serious and sometimes life-threatening eating disorders. The vast majority — more than 90 percent — of those afflicted with eating disorders are adolescent and young adult women.

Approximately 1 percent of adolescent girls develop anorexia nervosa, a dangerous condition in which a person can starve themselves to death.

Another 2 to 3 percent of young women develop bulimia nervosa, a destructive pattern of overeating followed by vomiting or other purging behaviors to control weight.

The consequences of eating disorders can be severe. Your bodily functions slow down and may cause your period to stop. If you think you may have an eating disorder, don’t hesitate to contact your healthcare provider to discuss the problem immediately.

Last Reviewed: October 2019