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Missed or Irregular Periods
Overview
Menstrual periods often occur every 21 to 35 days. But you may be different. Missed or irregular periods must be looked at in terms of what is normal for you. Menstrual periods often aren't regular during the first few years after your period starts. It may take several years for the hormones that control menstruation to reach a balance.
Periods also may not be regular when you get closer to perimenopause and menopause.
Menopause occurs when it has been 12 months since you had a period. 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 home pregnancy test as the first step to find out if you are pregnant.
If you aren't pregnant, other causes of missed or irregular periods include:
- Excessive weight loss or gain. Low body weight is a common cause of missed or irregular periods. Obesity also can cause menstrual problems.
- Eating disorders, such as anorexia or bulimia.
- Increased exercise. Missed periods are common in endurance athletes.
- Emotional stress.
- Chronic diseases, such as diabetes or irritable bowel syndrome.
- Medicines such as birth control methods. These may cause lighter, less frequent, more frequent, or skipped periods or no periods at all.
- Hormone problems, such as polycystic ovary syndrome.
They may cause a change in the levels of the hormones that the body needs to support menstruation.
- Illegal drug use.
- Problems with the pelvic organs such as an imperforate hymen or Asherman's syndrome.
- Breastfeeding. Regular periods may not resume until after you have finished breastfeeding.
- Primary ovarian insufficiency. This means you stop having periods before age 40. It can be caused by surgery, chemotherapy, or radiation therapy to the belly or pelvis.
Remember, you can still become pregnant even though you don't have periods. Practice birth control if you don't wish to become pregnant.
If you've skipped a period, try not to worry. It isn't uncommon to miss periods now and then. Unless you're pregnant, your cycle likely will return to normal next month.