What are menstrual irregularities?

For most women, a normal menstrual cycle ranges from 21 to 35 days.1 However, 14% to 25% of women have irregular menstrual cycles, meaning the cycles are shorter or longer than normal; are heavier or lighter than normal; or are experienced with other problems, like abdominal cramps.2 Irregular cycles can be ovulatory, meaning that ovulation occurs, or anovulatory, meaning ovulation does not occur.

The most common menstrual irregularities include:

  • Amenorrhea (pronounced ey-men-uh-REE-uh) or absent menstrual periods:3,4,5,6 When a woman does not get her period by age 16, or when she stops getting her period for at least 3 months and is not pregnant.
  • Oligomenorrhea (pronounced ol-i-goh-men-uh-REE-uh) or infrequent menstrual periods: Periods that occur more than 35 days apart.4
  • Menorrhagia (pronounced men-uh-REY-jee-uh) or heavy menstrual periods:3,4,7 Also called excessive bleeding. Although anovulatory bleeding and menorrhagia are sometimes grouped together, they do not have the same cause and require different diagnostic testing.7
  • Prolonged menstrual bleeding: Bleeding that exceeds 8 days in duration on a regular basis.4
  • Dysmenorrhea (pronounced dis-men-uh-REE-uh): Painful periods that may include severe menstrual cramps.8

Additional menstrual irregularities include:

  • Polymenorrhea (pronounced pol-ee-men-uh-REE-uh): Frequent menstrual periods occurring less than 21 days apart4
  • Irregular menstrual periods with a cycle-to-cycle variation of more than 20 days4
  • Shortened menstrual bleeding of less than 2 days in duration4
  • Intermenstrual bleeding: Episodes of bleeding that occur between periods, also known as spotting4


  1. American College of Obstetricians and Gynecologists (ACOG). (2012). FAQ: Abnormal uterine bleeding. Retrieved on May 24, 2016, from http://www.acog.org/Patients/FAQs/Abnormal-Uterine-Bleeding External Web Site Policy (PDF - 464 KB)
  2. Whitaker, L., & Critchley, H. O. D. (2016). Abnormal uterine bleeding. Best Practice & Research Clinical Obstetrics & Gynaecology, 34, 54–65. Retrieved June 23, 2016, from http://www.sciencedirect.com/science/article/pii/S1521693415002266 External Web Site Policy
  3. Sweet, M. G., Schmidt-Dalton, T. A., Weiss, P. M., & Madsen, K. P. (2012). Evaluation and management of abnormal uterine bleeding in premenopausal women. American Family Physician, 85, 35–43.
  4. Munro, M. G., Critchley, H. O., & Fraser, I. S. (2012). The FIGO systems for nomenclature and classification of causes of abnormal uterine bleeding in the reproductive years: Who needs them? American Journal of Obstetrics and Gynecology, 207(4), 259–265.
  5. Master-Hunter, T., & Heiman, D. L. (2006). Amenorrhea: Evaluation and treatment. American Family Physician, 73, 1374–1382.
  6. Practice Committee of the American Society for Reproductive Medicine. (2008). Current evaluation of amenorrhea. Fertility and Sterility, 90, S219–S225. doi:10.1016/j.fertnstert.2008.08.038.
  7. Apgar, B. S., Kaufman, A. H., George-Nwogu, U., & Kittendorf, A. (2007). Treatment of menorrhagia. American Family Physician, 75, 1813–1819.
  8. French, L. (2005). Dysmenorrhea. American Family Physician, 71, 285–291.

What are the symptoms of menstruation?

What are menstrual problems or irregularities?

How many women are affected by menstrual irregularities?

What causes menstrual irregularities?

How do health care providers diagnose menstrual irregularities?

What are the common treatments for menstrual irregularities?

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