What is polycystic ovary syndrome (PCOS)?

Polycystic ovary syndrome is when many eggs constantly produce low levels of hormones, which leads to a lack of ovulation.

Polycystic ovary syndrome is a condition during which the ovaries are not ovulating on a regular basis.

PCOS is serious in that, if not treated correctly, it leads to increased risks for type 2 and gestational diabetes, progressive obesity, cardiovascular disease, metabolic syndrome and uterine cancer. It is best to have PCOS diagnosed and treated as early as possible.

Dr. Humberto Scoccia, MD
OBGYN (Obstetrician & Gynecologist)
Polycystic ovary syndrome (PCOS) is a condition that causes infertility due to an abnormality in the release of the eggs each month (anovulation). Patients with PCOS have small cysts in the ovaries, which produce male hormones causing acne, excess hair and irregular menstrual cycles.

Polycystic ovary syndrome (PCOS), a hormone abnormality that affects as many as one in eight reproductive-aged women, is best known for its cosmetic effects—male-pattern hair growth and acne—but also is recognized for its gynecologic effects such as irregular menstruation and infertility. It is associated with both serious reproductive consequences and serious medical consequences, says Daniel Dumesic, M.D., UCLA obstetrician/gynecologist who specializes in reproductive endocrinology. The long-term health impact of PCOS and the fact that symptoms usually can be controlled with lifestyle changes and medications are strong reasons not to ignore early signs of the condition, Dr. Dumesic adds.

Polycystic ovary syndrome (PCOS) is a common problem, affecting one in ten girls and women, and results in irregular periods, acne, and extra hair growth. It occurs when hormone imbalances prevent eggs from maturing and being released from the ovaries each month; instead, the immature follicles form cysts in the ovaries. With no egg released, there’s no progesterone produced by the egg sac to balance the estrogen produced by the ovaries. This unopposed estrogen can lead to irregular periods--sometimes you have too few periods, others you may have periods with prolonged heavy bleeding; that's from a build up of excess lining in the uterus made by all that estrogen. Some of this surplus estrogen gets converted to the so-called male hormone testosterone (women’s bodies make it, too), causing acne and hair growth in unwelcome places. All that extra testosterone also increases the appetite, leading to weight gain in a majority of people with PCOS. Some patients also become resistant to the hormone insulin. This can bring about dark, velvety skin on the back of the neck, under the arms, or in the groin area, called acanthosis nigricans. While not dangerous, it is a sign of insulin resistance, which can lead to type 2 diabetes. Parents often mistake the skin discoloration for dirt, but it is actually extra pigment in the skin.
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Dr. David Forstein, DO
Fertility Specialist
PCOS, or Polycystic Ovarian Syndrome, is a condition that includes irregular menses and too much male hormone, explains David Forstein, MD, an obstetrician-gynecologist at Greenville Health System. Learn more in this video.
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Administration Specialist
Polycystic ovary syndrome (PCOS) is a hormonal condition found in women. It is very common and can appear any time after you begin your menstrual cycles. PCOS involves the formation of several cysts surrounding the outer rim of each ovary. The cause of PCOS is unclear but it may be related to high levels of male hormones called androgens and to insulin resistance. PCOS causes several different physical and emotional symptoms and can lead to some serious conditions, including infertility.
Dr. Kevin W. Windom, MD
OBGYN (Obstetrician & Gynecologist)
Polycystic ovarian syndrome is a hormonal condition that is caused by abnormal ovarian function. There are 2 main cell types in the ovary. There are cells that make estrogen and also grow eggs prior to ovulation, and there are other cells that make male-like hormones. Polycystic ovarian syndrome is where there is a predominance of small cysts throughout the ovary that are making male-like hormones. These cysts make is very difficult for an egg to mature and for a woman to ovulate. Because these cysts predominate the ovary, they cause a hormonal imbalance where there is excess testosterone and other male type hormones. This causes a change in their insulin and glucose metabolism and can predispose them to weight gain and possible diabetes. Also, the excess male-like hormones can cause a patient to gain weight in their abdominal area as well as have abnormal facial hair growth and pubic hair growth. Because of the hormonal irregularities, most patients with polycystic ovarian syndrome do not ovulate and have amenorrhea (quit having periods).
Polycystic ovary syndrome (PCOS) is a very common hormone disorder in women, a leading cause of infertility, and one of the most underdiagnosed diseases in the United States. PCOS is characterized by a myriad of seemingly unrelated symptoms and may include irregular or absent periods, lack of ovulation, weight gain, acne, excessive facial hair and infertility. Even more serious, women with PCOS may be at higher risk for developing cardiovascular disease, Type 2 Diabetes, and endometrial cancer, especially if PCOS is left untreated.

Surprisingly, most women with PCOS don't even know they have it. Less than 25 percent of women with PCOS have actually been diagnosed, largely because women and their health care providers tend to look at the wide variety of symptoms individually rather than collectively. Most women are never officially diagnosed until they begin struggling with infertility and seek help in getting pregnant.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.