It is not unusual for girls to experience irregular periods when they first start menstruating. A girl might skip a period and then have a longer or shorter period. Then she might go back to a regular period. Also, some may have irregular periods throughout their lives.

There are several reasons why a girl might miss a period, including:

• Her period cycle hasn’t become regular yet
• Stress
• Strict dieting, over-exercising or being a competitive athlete
• Medication
• Gaining or losing a lot of weight over a short period of time

A missed period can also be the first sign of a pregnancy. If a girl has had unprotected vaginal intercourse with a guy, then it is important to find out whether she is pregnant as soon as possible. She can get a home pregnancy test from a store or, better yet, make an appointment with her doctor or clinician.

Learn more about the menstrual cycle or find a clinic near you.