Dismiss Modal

Types

Polycystic Ovary Syndrome

Choose a preferred language

Polycystic ovary syndrome (PCOS) causes harmless, small cysts in the ovaries and other symptoms. PCOS is caused by certain hormones being out of balance. The word syndrome means a group of symptoms. Women with PCOS may have no periods, irregular periods, or very long or heavy periods.


Your ovaries

Women store their eggs in their ovaries. Each egg is in a capsule called a follicle. Normally during the reproductive years, one follicle grows to make a mature egg each month. This egg is released during ovulation and the follicle dissolves.

Front view of female reproductive tract with insets showing normal ovary and polycystic ovary.


Hormones out of balance

With PCOS, the hormones that control ovulation are out of balance. These include estrogen, progesterone, and androgen. As a result, ovulation may not occur. Instead, the follicle stays enlarged. This is a fluid-filled sac called a cyst. Over time, the ovaries fill with many small cysts. This is why they are called poly or many cystic ovaries. In some women, the ovaries also make too much androgen.


Symptoms of PCOS

Women with PCOS may also have one or more of these symptoms:

  • Acne

  • Hair growth on the face and other parts of the body

  • Patches of thick, velvety, dark skin (acanthosis nigricans), often on the neck or groin area

  • Trouble getting pregnant (fertility problems)

  • Weight gain, often around the waist 

Women with PCOS are also at greater risk of having cancer of the uterine lining, diabetes, and heart disease.

Featured in

© 2000-2025 The StayWell Company, LLC. All rights reserved. This information is not intended as a substitute for professional medical care. Always follow your healthcare professional's instructions.

Find the right providers for your needs.

CalOptima Health works with thousands of Orange County providers, including doctors, specialists, health networks, medical groups and more.

Find a Doctor

Get Care Now

Get Care Now
Related Articles
Read article
Metabolic Conditions
Thyroid Disorders in Those Born Female

Detailed information on thyroid disorders and how they affect women, including puberty, pregnancy, and menopause.

Read article
OB/GYN
Understanding Ovarian Cystectomy

An ovarian cystectomy is a surgery that removes a cyst from your ovaries. It's usually done only if the cyst is large or painful.

Read article
OB/GYN
Sonohysterography

Sonohysterography is a procedure to look at the inside of the uterus. It's a safe, painless test that uses sound waves and a computer to create images. It doesn't use radiation. Read on for details about this test.

Read article
Breast Health
Mammogram

A mammogram is a way to look at your breast using X-rays. It is used to find and diagnose breast disease in women. Read on to learn more details about when and why to get a mammogram, and what you can expect when having it done.