Menstrual periods typically last four to seven days and occur roughly every 28 days. Examples of irregular periods include periods that occur fewer than 21 days or more than 35 days apart, missing three or more periods in row, and menstrual flow that’s much heavier or lighter than usual.
Most women and people assigned female at birth (AFAB) have menstrual periods that last four to seven days. Your period usually occurs every 28 days, but normal menstrual cycles can range from 21 days to 35 days. In fact, the average cycle length is 29 days. Many things cause irregular periods (or irregular menstruation) such as changes in hormone levels, stress, certain health conditions, medications and more.
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Your period is still considered “regular” even if it varies slightly from cycle to cycle. Examples of irregular menstruation include:
Your menstrual cycle may not always be predictable — and that may be OK. It’s normal to have slight variations in cycle length or have a menstrual period that seems slightly heavier or lighter in flow than your previous period. Menstrual irregularities are fairly common, and you don’t have to be able to predict your cycle to the exact day for it to be considered “normal.”
There are many causes of irregular periods, ranging from stress to more serious underlying medical conditions.
Certain health conditions are associated with missed menstrual periods. They include:
Disruptions or changes in your daily routine can have an impact on your menstrual cycle. Some examples of lifestyle factors include:
Certain medications, complications of pregnancy or breastfeeding (chestfeeding) may also cause your period to be irregular. Other causes include:
If you sense changes in your menstrual cycle, begin keeping records of when your periods begin and end. Note symptoms, the amount of flow or if you experience cramping, bleeding between periods or passing large clots. These are all helpful to share with your healthcare provider.
To diagnose irregular periods, your provider will ask you about your menstrual cycle and medical history. They’ll perform a physical examination, including a pelvic exam. They might also order certain tests, including:
The treatment for irregular periods depends on the underlying cause.
Medications are often the first treatment for irregular periods. If medication doesn’t help, your provider may recommend surgery. Possible medications include:
There are surgical treatment options depending on your condition, age and whether you want to get pregnant in the future. Surgical treatments for irregular periods include:
Here are some recommendations for self-care:
Contact a healthcare provider if you have painful or irregular periods or any of the following symptoms:
You should also see your provider if you think you might be pregnant.
Skipping one or two periods isn’t ideal, but it’s not too concerning. Take a look at any changes in your life recently. Things like stress, a new workout routine, losing or gaining weight, or changing birth control can all impact your cycle. Call your healthcare provider if you miss your period for three or more months in a row or if you experience other unusual symptoms during your next period.
Slight delays in your period are typically OK. Some people are able to predict their period to the exact day, while others can’t. Contact your provider if you notice a sudden change in the time between cycles or the duration (days) of your period, especially if it’s significant. This doesn’t always indicate a problem, but it’s a good idea to get it checked out.
Irregular periods are more common when you first begin menstruating (around age 9 to 14) or during perimenopause (around age 50 or just before menopause).
Irregular periods may be nothing to worry about because some variation in menstruation is normal. What’s normal for you may be different from what’s normal for your closest friends. However, certain symptoms could be a sign of a bigger problem.
Contact your gynecologist if you’re concerned about your menstrual cycle or if you’re trying to get pregnant and have unpredictable periods (this can make getting pregnant difficult). They’ll be able to tell you what’s normal and if treatment is needed.
A note from Cleveland Clinic
There are many causes for irregular periods and menstrual irregularities. Contact your healthcare provider if you experience drastic changes in your menstrual cycle or your period becomes extremely painful. Most causes of irregular periods aren’t serious and are treatable with medication by your healthcare provider. Keep in mind that slight variations between cycles or in the duration of your period usually aren’t a cause for worry. Everyone’s “normal” is different. If you sense something is off with your menstrual period, write down what’s changed and your symptoms so you can talk to your provider.
Last reviewed by a Cleveland Clinic medical professional on 01/18/2023.
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