Polycystic Ovary Syndrome

(PCOS; Stein Leventhal Syndrome; Polyfollicular Ovarian Appearance; Hyperandrogenic Anovulation; Polycystic Ovarian Disease; PCO; PCOD)


Polycystic ovary syndrome (PCOS) is a hormone problem in women. With PCOS, the ovaries make follicles but they don’t mature and release an egg each month. The follicles can turn into fluid-filled sacs called cysts.

Ovary and Fallopian Tube
Ovarian Cyst

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The cause is not known. Insulin resistance seems to play a role. It creates high levels of insulin. This causes the ovaries to make too much of a male hormone called androgen. This can result in male features. It can stop ovulation from happening. It can lead to large ovaries with many cysts.

Risk Factors

Factors that may raise your chance of PCOS:

  • People in your family with PCOS
  • Obesity


Some women may not have symptoms. If you do, they may be:

  • Inability to become pregnant
  • Irregular or no menstrual periods
  • Obesity
  • Undesired hair growth
  • Hair loss from the scalp


The doctor will ask about your symptoms and health history. A physical exam will be done.

You may have:

  • An ultrasound to view your ovaries
  • Blood tests to measure glucose, cholesterol, and hormone levels
  • Urine tests to check for pregnancy.


The goal of treatment is to target insulin resistance. The treatment you have depends on whether you want to become pregnant. You may need:

  • Medicine to:
    • Manage abnormal hair growth
    • Treat acne
    • Improve insulin resistance
    • Bring on ovulation if you want to become pregnant
    • Regulate menstruation
  • Lifestyle changes:
    • Weight loss if you are overweight
    • Healthy eating
    • Exercise


PCOS can't be prevented.


The American Congress of Obstetricians and Gynecologists

Polycystic Ovarian Syndrome Association


The Society of Obstetricians and Gynaecologists of Canada (SOGC)

Women's Health Matters


ACOG Committee on Practice Bulletins—Gynecology. ACOG Practice Bulletin No. 108: Polycystic ovary syndrome. Obstet Gynecol. 2009;114(4):936-949. Reaffirmed 2015.

Baillargeon JP. Use of insulin sensitizers in polycystic ovarian syndrome. Curr Opin Invetig Drugs. 2005:6(10):1012-1022.

Glintborg D, Altinok ML, Mumm H, et al. Body composition is improved during 12 months' treatment with metformin alone or combined with oral contraceptives compared with treatment with oral contraceptives in polycystic ovary syndrome. J Clin Endocrinol Metab. 2014;99(7):2584-2591.

Li XJ, Yu YX, Liu CQ, et al. Metformin vs thiazolidinediones for treatment of clinical, hormonal and metabolic characteristics of polycystic ovary syndrome: A meta-analysis. Clin Endocrinol (Oxf). 2011;74(3):332-339.

Polycystic ovary syndrome. American Academy of Family Physicians Family Doctor website. Available at: http://familydoctor.org/familydoctor/en/diseases-conditions/polycystic-ovary-syndrome.html. Updated April 1, 2015. Accessed July 25, 2018.

Polycystic ovary syndrome. EBSCO DynaMed Plus website. Available at:http://www.dynamed.com/topics/dmp~AN~T116286/Polycystic-ovary-syndrome. Updated June 18, 2018. Accessed July 25, 2018.

Polycystic ovary syndrome (PCOS). Endocrine Society Hormone Health Network website. Available at: http://www.hormone.org/diseases-and-conditions/womens-health/polycystic-ovary-syndrome. Accessed July 25, 2018.

Stadmauer L, Oehninger S. Management of infertility in women with polycystic ovary syndrome: A practical guide. Treat Endocrinology. 2005;4(5):279-292.

Last reviewed May 2018 by EBSCO Medical Review Board Kathleen A. Barry, MD  Last Updated: 7/25/2018