How Many Days of Bleeding Are Typical During Menstruation?

At some point, most women wonder if their menstrual cycle is normal. It's a natural question that you may have, too, especially if your period varies in length from one monthly cycle to the next.

Normal menstruation can last from one to seven days. Most women with regular menstrual cycles have periods that last an average of three to five days.

It's perfectly normal for your period to vary slightly from cycle to cycle. You should remain watchful of extremes, meaning very light or very heavy periods.

They can be a sign of an underlying health issue. And excessive bleeding can lead to anemia (low red blood cells).

This article defines what "normal" menstruation is and the three factors most likely to affect the length of a normal period. It also explains what lengthy and/or heavy periods are and why you should be alert to them.

Normal Menstruation

Your period occurs when the lining of your uterus sheds. Periods are triggered by ovulation, or when an egg is released from an ovary.

Typically, if you don't get pregnant during a cycle, your period will arrive 14 days after you ovulate.

Many women "compare notes" about their periods. But every person is different, and so is their menstrual cycle.

Still, it's not normal to bleed for more than seven days every month or not bleed at all once you have passed menarche. This is the formal name for the onset of menstruation during puberty.

Long Or Heavy Periods

Heavy bleeding is a sign to contact your healthcare provider. (One such cycle is OK, but two or three are not.) So what does "heavy" mean?

• Soaking one or more tampons or pads every hour for several hours in a row
• Wearing more than one pad at a time to absorb bleeding
• Having to change pads or tampons overnight (a time when bleeding often slows)
• Having periods that include blood clots the size of a quarter or larger

Factors Affecting Period Length

Several factors could affect the length of your period:

Medical Conditions

Medical issues that change the thickness of the endometrium (uterine lining) or the number of blood vessels within it play a role in how many days your period lasts.

This is because your menstrual flow consists of the shedding endometrium, as well as blood from the little vessels that are exposed afterward.

Heavy and/or long periods could be a sign of:

• A bleeding disorder or medication that thins the blood (like aspirin)
• Ectopic pregnancy, when a fertilized egg attaches in a fallopian tube. or miscarriage
• Endometriosis, when endometrial tissue grows outside the uterus
• Hypothyroidism, when the thyroid gland fails to make enough thyroid hormones
• Pelvic inflammatory disease, an infection that affects the reproductive organs
• Polycystic ovary syndrome, a hormonal disorder
• Uterine cancer

It's understandable that the thought of some of these conditions may spark fear. See your healthcare provider if you have heavy or long periods, so they can find the cause and treat it.

Age

During the first few years after the start of menstruation, you may experience unpredictable bleeding patterns. The reason? You may not be ovulating regularly yet.

Ovulation requires a complex interaction between your brain, ovaries, and hormones. It can take some time for your body to get the balance right.

After a first period, some people bleed for more than the average number of days and/or skip a few periods in a row. Menstruation usually normalizes in about three years.

You may have irregular periods as you approach the end of your reproductive years (at some point in your 40s). This is known as perimenopause, or the menopausal transition.

This is a time when estrogen production begins to decline. As estrogen levels drop, there is less buildup of the uterine lining. Lighter, shorter, and maybe even irregular periods result.

Birth Control

Most women report having lighter and shorter periods when they use birth control. And this goes for both combined hormonal contraceptives—those that deliver both estrogen and progesterone—and progesterone-only contraception.

This happens because the synthetic hormones in the birth control override the hormones produced by your ovaries.

Combined hormonal contraceptives include the:

• Oral contraceptive pill
• Contraceptive patch
• Contraceptive ring

Progesterone-only methods include:

• Some intrauterine devices (an IUD like Mirena)
• A contraceptive implant (for example, Nexplanon) 
• An injectable contraceptive (like Depo-Provera)

As you might guess, women who regularly have heavy or long-lasting periods sometimes are prescribed birth control to get them under control.

Summary

"Normal" periods last from one to seven days, with the average lasting between three and five days. You'll soon find (if you haven't already), that what's normal for you may not be normal for a close friend or family member. So focus on any changes in your own cycle.

Medical conditions, age, and birth control can affect the length and intensity of your period. Heavy or lengthy periods could be a sign of a problem. Take note and call your doctor if you have several in a row.

A Word From Verywell

When it comes to your period, there is a small range of what's considered normal in terms of duration and frequency. Once you've started menstruating, discuss any changes in your cycle with your healthcare provider. Two changes in particular are worth sharing: if you miss your period or if your period lasts longer than seven days.