Menstruation is one of the big stages in puberty for girls and is one of multiple signs indicating a girl is starting to become a woman. As with the other changes that come with puberty, menstruation is confusing for many girls. Some are anxious or afraid while others are excited and can’t wait for their period to arrive. Many teens don’t completely understand the female reproductive system and this makes it even more challenging to understand the menstrual cycle. Read on to learn when teenage menstrual cycle is normal and when you should be worried.

Normal Teenage Menstrual Cycle

Girls start puberty at different ages and the same is true for their menstrual cycle. Some girls start their period as young as at 10 years old but others won’t start their period until they are 15.

A menstrual cycle refers to the period of time between periods and it is counted starting at the beginning of the period. Although people think of the standard cycle as 28 days, some girls will have 24 day cycles with others having 30 day cycles or longer ones. After menarche (first menstrual bleeding), menstrual cycles tend to be between 21 and 45 days and this number shortens in a few years to 21 to 35 days.

What About Irregular Teenage Menstrual Cycle?

It is common for girls that are just starting to menstruate to experience irregular periods. The body needs time to get used to the changes so it is possible to have a 28 day cycle for several months and then skip a month. In most cases the menstrual cycle will become regular within several years, but some women experience irregular cycles as well.

Your hormones will affect the length of your period as well as your flow. While you are growing, your hormones will fluctuate and that in turn can cause large variations in terms of flow and duration between cycles.

Eventually, your body will find a regular cycle. As a teenager, you simply want to make sure you have a period at least once every three months. You can also talk to your doctor about concerns.

Symptoms That May Occur in Teenage Menstrual Cycle


Some girls have emotional or physical changes close to their periods. Over half of menstruating women have cramps within their first few days of their cycle. Doctors suspect these are due to prostaglandin which is a chemical that leads to the contraction of the uterine muscles.

Menstrual cramps vary by girl and may be sharp and intense or dull and achy. In some cases you can feel them in the back in addition to the abdomen. Usually they will become more comfortable or completely disappear as a girl ages.

PMS and Pimples

Some girls get easily irritated or sad about a week before their cycle or within the first few days of it. Others get angry or cry more easily than normal while yet others have food cravings. These emotional changes are usually due to PMS (premenstrual syndrome).

Many girls also experience acne flare-ups at specific points in their cycles due to hormone. This problem tends to decrease as you age.

In the following video, the girl shares her experience of getting period and how she responds. Learn about the tips for coping with teenage menstrual cycle:

The Amount and Duration of Teenage Periods

Just like everything else with a menstrual cycle, the amount of time it lasts can vary greatly with the duration ranging from two to seven days. Similarly the quantity of blood (or menstrual flow) will also vary.

Some girls are concerned at first that they may be losing too large a quantity of blood. In reality, the average person only loses about 30 milliliters (or two tablespoons) during their entire cycle. Bleeding should not be a concern unless you have von Willebrand disease or something similar. Most teens find that they have to change their pads between three and six times each day although this number can increase at the heaviest points.

When Should You Worry?

If you are concerned about your teenage menstrual cycle, then you may want to know if it is normal. You should talk to your doctor in the following situations:

  • Your period continues over a week
  • You need to change your pad very frequently (every one or two hours)
  • There is more than three months between cycles
  • There is bleeding between cycles
  • There is excessive pain during or before your period
  • Your periods started regular then changed to irregular

Why Do You Have Missed Period When Not Pregnant?

Keep in mind that birth control pills will only be effective if you take them regularly and condoms are only effective 99% of the time. Despite this, that doesn’t necessarily mean that if you missed your period you are pregnant. Here are some other possible reasons:

  • Excessive Exercise. Excessive exercise may lead to less bleeding, a decrease in the number of periods you get, or your periods completely stopping. Most of the time your menstrual cycle will go back to normal within a few months after reducing your exercise. If your period completely stopped for six months, talk to your doctor to rule out medical problems.
  • Birth Control Pills. Some doctors will recommend birth control pills to regular their periods. In some cases, however, this will lead to a missed period. This is especially true of hormonal methods that contain progesterone, a hormone.
  • Stress. Although low to mild stress is normal in life, higher amounts may negatively affect your cycle. If you have too much stress, it is possible to miss a period or have an irregular one.
  • Eating Disorders. Eating disorders such as bulimia or anorexia may slow down your body’s functions, leading to the period stopping completely. If you have an eating disorder, you should always seek help from an adult or doctor.