Missed or Irregular Periods

Most women have between 11 and 13 Reference menstrual Opens New Window periods each year. You may be different: You may have more or fewer. Missed or irregular periods must be looked at in terms of what is normal for you.

Menstrual periods are often irregular during the first few years after Reference menstruation starts. It may take several years for the Reference hormones Opens New Window that control menstruation to reach a balance.

Menstrual periods also may be very irregular at the other end of the menstrual years. Many women realize that they are approaching Reference perimenopause Opens New Window and Reference menopause Opens New Window when their otherwise regular periods become irregular. Menopause occurs when it has been 12 months since you have had a menstrual period.

Reference Pregnancy is the most common cause of a missed period. If you might be pregnant, treat yourself as if you are pregnant until you know for sure. Use a Reference home pregnancy test Opens New Window as the first step to finding out whether you are pregnant.

If you are not pregnant, other causes of missed or irregular periods include:

• Excessive weight loss or gain. Although low body weight is a common cause of missed or irregular periods, obesity also can cause menstrual problems.
• Eating disorders, such as Reference anorexia Opens New Window or Reference bulimia Opens New Window. For more information, see the topic Reference Anorexia Nervosa or Reference Bulimia Nervosa.
• Increased exercise. Missed periods are common in endurance athletes.
• Emotional stress.
• Illness.
• Travel.
• Reference Medicines such as Reference birth control methods, which may cause lighter, less frequent, more frequent, or skipped periods or no periods at all.
• Hormone problems. This may cause a change in the levels of the hormones that the body needs to support menstruation.
• Reference Illegal drug Opens New Window use.
• Problems with the Reference pelvic organs Opens New Window Reference Opens New Window, such as Reference imperforate hymen Opens New Window, Reference polycystic ovary syndrome Opens New Window, or Reference Asherman's syndrome Opens New Window.
• Breast-feeding. Many women do not resume regular periods until they have completed breast-feeding.

Remember, you can still become pregnant even though you are not menstruating. Practice birth control if you do not wish to become pregnant.

Premature ovarian failure is when you stop menstruating before age 40. Surgery, Reference chemotherapy Opens New Window, and Reference radiation therapy Opens New Window to the abdomen or pelvis may cause premature ovarian failure.

Other diseases such as Reference irritable bowel syndrome Opens New Window, Reference tuberculosis Opens New Window, Reference liver disease Opens New Window, and Reference diabetes Opens New Window can cause missed or irregular periods, although this is rare. But if any of these diseases are present, you will usually have other symptoms besides menstrual irregularities.

If you've skipped a period, try to relax. Restoring your life to emotional and physical balance can help. Many women miss periods now and then. Unless you are pregnant, chances are your cycle will return to normal next month.

Reference Check your symptoms to decide if and when you should see a doctor.

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This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Reference Terms of Use. Reference How this information was developed to help you make better health decisions.