Irregular Periods In Teenagers: What Is Normal And When To Seek Help

Image: iStock


Irregular periods in teens are normal in most cases and may become regular over a few years (1). However, you may have to consult a doctor to ensure that no underlying conditions are causing irregular menstruation in your teenager.

Read this MomJunction post to know more about the causes, complications, diagnosis, and treatment of irregular periods in teens and when you need to be concerned.

What Are Irregular Periods?

A menstrual cycle is considered irregular if it lasts longer or shorter than the average. Teenagers may have variations in menstrual cycles due to hormonal influences. The interval between regular periods ranges from 20 to 45 days, with an average of 32 days, during the first two years after the menarche (first period). Later on, the typical length of cycles can range from 21 to 34 days, with an average of 28 days (2).

Irregular periods are different from amenorrhea (missed period). However, the factors contributing to irregular periods may also play a role in the development of amenorrhea. Amenorrhea can be of two types (1):

  • Primary amenorrhea, where a girl does not get her first period by the age of 15
  • Secondary amenorrhea, where, after starting to menstruate, she misses the period for more than three months. This may be due to physical or emotional factors.

Causes Of Irregular Periods In Teens

In most cases, it is normal for teenagers to have irregular periods as part of bodily changes, and they resolve as they get older.

The following are the reasons for irregular menstruation in a teen (3):

  1. Medications
  2. Too much workout
  3. Underweight or overweight
  4. Reduced calorie content and nutrition in food
  5. High carbohydrate diet
  6. High or low thyroid hormone levels
  7. Excess androgen
  8. Stress
  9. Eating disorders
  10. Drug use

Heavy menstrual bleeding and abnormal uterine bleeding may occur in teens due to conditions such as blood coagulation disorders, ovarian problems, or hormonal variations.

Note: Amenorrhea or missed periods can be caused by the above-listed factors. Seek medical help if your teen has menstrual irregularities or missed menstruation.

Complications Of Irregular Periods In Teens

Irregular periods in a teen may increase the risk of developing (2):

  • Anemia: If your teen has frequent and heavy menstruation, there is a risk of anemia due to blood loss.
  • Thinning of bones: Often, irregular or missed periods are associated with low estrogen levels. This may result in osteoporosis (thinning of the bones) over time and make them vulnerable to fractures.
  • Fertility problems: Irregular periods could continue until the reproductive years and may interfere with fertility.

Although irregular periods are normal in most teens and disappear after a few years, it could impact the quality of life. Seek medical help to identify and treat the underlying causes to prevent complications.

When To See A Doctor?

Seek medical consultation at menarche itself. You may also visit the doctor if you are concerned about the irregular cycles in your teen.

The following changes may require the consultation of a gynecologist (3):

  • Regular cycle changes to irregular
  • Periods occur in less than 20 days
  • There is more than 45 days gap between cycles
  • Menstruation lasts more than seven days
  • Experiences severe cramping or abdominal pain
  • Bleeds between periods
  • Has amenorrhea (no menstruation for 90 days or three months)
  • Has menorrhagia (heavy bleeding), soaking more than one pad in one to two hours
  • A personal or family history of bleeding disorders
  • A possibility of pregnancy
  • Excess body and facial hair growth

Early diagnosis and treatment may help to improve the outcome if a teenager has menstrual problems due to some underlying conditions.

Diagnosis Of Irregular Periods In Teenagers

Your doctor diagnoses irregular periods by evaluating the patterns of cycles and health history. It will be easier to diagnose if you have a menstrual chart or calendar.

Your doctor may order the following tests to identify the causes of irregular menstruation (4):

  • Blood tests: The hormonal levels and coagulation time of blood can be obtained from blood tests. These may also help identify pregnancy and complications of heavy bleeding, such as anemia.
  • Pelvic ultrasound: The sonographic imaging of the pelvic area could help identify any physical abnormalities in the reproductive organs.

Note: Charting menstrual days can be helpful to identify irregularities of cycles. You may encourage your teen to do this on a menstrual calendar.

Treatment For Irregular Periods In Teens

Irregular periods may not require treatment in most teens. The doctor may suggest lifestyle changes such as following a healthy diet, exercising, etc., to maintain healthy body weight and nutritional status. However, if the menstrual irregularities interfere with her quality of life and can not be managed, hormonal treatment, including cyclic progesterone and oral contraceptives, may be prescribed.

If her period problems are due to underlying diseases, your teen may require treatment for those.. This could include a correction of the thyroid hormones, injection of clotting factors for bleeding disorders, psychotherapy, and medications for eating disorders.

Surgical interventions are recommended for menstrual irregularities caused by structural abnormalities  (5).

Home Remedies For Irregular Periods In Teens

If your teen has irregular menstruation due to lifestyle factors, you may encourage them to develop new healthy habits.

The following lifestyle changes could help reduce the chances of menstrual abnormalities (6):

  • Performing moderate-intensity exercises
  • Maintaining a healthy weight
  • Consuming less sugar and carbohydrates
  • Including nutritious foods in the diet
  • Managing stress

Encourage your teen to follow a healthy lifestyle. You may explain to them the importance of good habits.

Even though your teen has irregular cycles, certain signs and symptoms may help them know when they will have their menstruation. You may ask them to notice the bodily changes such as back pain, acne, headaches, bloating, mood swings, etc., to understand that they are nearing the cycle and plan their activities accordingly.

You can also advise your daughter to carry some pads or tampons in a bag or purse to manage unexpected periods if they have irregular cycles.

Do you have an experience to share? Let us know in the comments section below.


MomJunction's articles are written after analyzing the research works of expert authors and institutions. Our references consist of resources established by authorities in their respective fields. You can learn more about the authenticity of the information we present in our editorial policy.
1. Period problems; Women’s Health; The United States Department of Health & Human Services
2. Paula J. Adams Hillard; Menstruation in Adolescents: What’s Normal?; The Medscape Journal of Medicine (2008).
3. Menstruation in Girls and Adolescents: Using the Menstrual Cycle as a Vital Sign; The American College of Obstetricians and Gynecologists
4. Diane Sacks; Common menstrual concerns of adolescents; Pediatrics Child Health (1998).
5. What are the common treatments for menstrual irregularities?; The Eunice Kennedy Shriver National Institute of Child Health and Human Development
6. Exercise, diet & periods; The Royal Women’s Hospital; Victoria Australia

Recommended Articles: