Understanding Irregular Periods: Causes & When to See a Doctor

A woman's menstrual cycle can fluctuate in length from time to time for a variety of reasons. Although these fluctuations are not usually a sign of a larger health issue, you should consult your doctor if it happens regularly.

Time Frame

• On average, a woman's menstrual cycle lasts 28 days from start to finish, but a cycle can range from 23 to 35 days and still be considered normal.

Function

• The overall function of a woman's menstrual cycle is to prepare the body for pregnancy. If fertilization does not occur, menstrual bleeding removes the unfertilized egg from the womb.

Considerations

• A change in lifestyle, diet, or behavior can directly affect a woman's cycle. Weight gain or loss, a change in exercise routines, or a drastic change in eating habits can cause a woman's cycle to start earlier or later, depending upon her hormone levels.

Misconceptions

• Many woman assume that their cycles are always exactly the same length each month. However, most women's cycles fluctuate by at least a day or so one or more times per year. Charting your cycle on a calendar can help you to see the changes.

Warning

• If you experience a dramatic change in your cycle or if it is consistently getting shorter, you should schedule an exam to find the cause of the change.