How Long Should a Period Last?

We’ve all had that friend who chimes in while we’re lamenting over our painful, seemingly endless periods. She says things like, “Oh, mine aren’t that bad” or “Are you sure that’s normal? My period only lasts X number of days.”

But what exactly is normal? Menstrual cycles that culminate in short, light flows? Or longer, heavier periods?

The answer might be more complex than you think.

Tracking Your Periods

First, it’s important to know just how long your menstrual cycle and periods actually are. You can track your menstrual cycle the old-school way by marking the first day you start bleeding one month and the first day you start bleeding the next month, then noting how many days pass between these dates. Doing this consistently will tell you how long your menstrual cycle tends to last.

Or you can save some time by downloading any number of popular apps to track your periods. These make it easier by allowing you to use your phone, tablet, or computer to monitor your cycle, record your symptoms, and become more aware of when you’ll experience things like PMS or ovulation.

Most women will come up with a cycle that is an average of 28 days, but not all of us have the same cycles. Once you know how long your menstrual cycle is, you can keep a look out for potential pregnancies or plan ahead for your periods. This way you’ll have pads and tampons on hand (or your menstrual cup, if you’ve gone that route). Many women try to avoid scheduling vacations or other important days during the time they’ll have their periods.

How Long Should a Normal Period be?

When it comes to the frequency, length and flow of your monthly visitor, a general rule of thumb is that normal periods are defined as what’s normal for you. But being knowledgeable about your menstrual cycle can help you identify when things go awry.

You get your period when your uterus sheds its lining – also known as its endometrium. Part of your menstrual flow is blood and part of it is endometrium. Most women get their period about 12 to 16 days after ovulation.

The average menstrual cycle is 28 days. A “normal” period can last anywhere from two to seven days but is usually only three to five days.

First Periods

Most of us start our periods between the ages of twelve or thirteen, but some girls start younger and some start later. Usually, a girl’s cycle will start about two or three years after her breasts begin to develop and a year after a noticeable growth spurt.  

If you’re a teenager and experiencing your first period, it may take up to two years for your menstrual cycle to become predictable and regular. Your cycle also may run longer than the 28-day average seen in adults.

Young women should check in with their doctor if they haven’t had their first period by the time they turn fifteen years old.

Factors That Can Affect Your Period’s Length

Factors like biology, stress, and travel can affect when your period comes and the number of days it lasts. They can also have an impact on the amount of bleeding and severity of cramps that you experience.

Your age can affect the amount of hormones in your body; for example, as we get older, we produce less estrogen. This can lead to a lighter and shorter period. However, if a woman has a polyp or fibroid in her uterus, she may experience heavier bleeding for a longer number of days.

Lighter Periods With Birth Control Pills

Those of us who use birth control pills often have shorter periods with a lighter flow. Traditional pill packs feature several “non-active” or placebo pills that trigger your period. Women can prevent their periods by skipping the placebo pills and diving right into a new pack, or they can take a medication like Seasonale, which is specifically designed to allow women to avoid the majority of their periods.

Since the introduction of Seasonale in 2003, scads of new birth control pill formulas have come onto the market that allow you to skip most of your periods. And when you do eventually have a period on these medications, you can have a lighter, shorter one.

It might take a few months after you first start taking birth control pills until your periods normalize. In fact, the most common cause of irregular bleeding is missed pills.

Long Periods

There’s no reason to be concerned if your period occasionally lasts longer than seven days. Your extended flow could be caused by normal hormonal fluctuations or your body adjusting to a change in your lifestyle.

But there might be more going on if you regularly have long, heavy periods. Underlying health conditions could be affecting your menstrual cycle. Most of them are treatable, and simple medical treatments could greatly improve your quality of life. Other rarer disorders may be life threatening, so it’s a good idea to check in with a doctor when your periods are consistently abnormal.

Short Periods

What makes a period “too short”? As long as a short menstrual period is part of a regular pattern and fits within a range of two to seven days, you’re considered to have normal periods.

Periods that last less than two days or that come at irregular intervals could be caused by a variety if physical factors, like polycystic ovary syndrome (PCOS) or perimenopause. Light spotting can also be a symptom of pregnancy. If you notice a radical change in your cycles, visit your OBGYN to make sure all your lady bits are working as they should.

Younger women may have short and irregular periods, and older women approaching menopause may also experience irregular or short menstrual periods.

When to Get Checked Out

Normal cycles last between 24 to 35 days. Some teens might have shorter cycles of only 21 days, and others might go as long as 45 days between periods. Adults can have a range of between 21 to 35 days. See a doctor if your cycle falls outside of these ranges. Also, if you’ve been menstruating for more than two years and your period hasn’t become regular, visit a healthcare provider.

Being sick or under stress can cause a delayed period or for you to skip it altogether. However, if you miss a period and are sexually active, definitely get checked out for a possible pregnancy. Also, visit a healthcare professional about your period if:

• You haven’t gotten your first period by age 15
• You don’t menstruate for more than 90 days
• Your periods start to be very irregular after having previously been regular
• Your period lasts for more than seven days
• Your menstrual flow is heavier than usual
• You experience bleeding between periods
• You experience horrible pain during menstruation
• You suddenly get a fever and feel ill after using tampons

If your irregular or short menstrual cycle is a new development and not your typical pattern, it’s always a good idea to consult with your doctor.