Polycystic Ovary Syndrome (PCOS)

Polycystic Ovary Syndrome (PCOS)

Polycystic ovary syndrome (PCOS) is a condition characterized by infrequent or absent menstrual periods accompanied by increased hair growth or acne in women. The name is derived from the typical presence of multiple small fluid-filled cysts (follicles) within the ovaries that contain immature eggs. Although the characteristic appearance of the polycystic ovary was first described in the mid-1800s, its significance was not truly appreciated until 1935 when Drs. Irving Stein and Michael Leventhal first associated this entity with infertility, ovulation problems and excessive hair growth. For many years, PCOS was known as the Stein-Leventhal syndrome.


The specific cause of PCOS is not well understood and may be genetic, although the specific mode of inheritance as well as the proportion of cases of PCOS that occur through inheritance is not known. There is thought to be a range of possible abnormalities in women with PCOS that ultimately result in an increased production of androgen (male hormone) from the ovary and/or adrenal gland. The increased level of androgen, in turn, inhibits the normal maturation of a woman's eggs and the accompanying growth of the follicles (cysts) that contain the eggs, leading to the typical multi-cystic appearance of the ovaries. In addition, the increase in androgen production results in acne and/or excessive growth of hair in areas not typical for women, such as the face and abdomen.

Ovulatory Dysfunction

Because the eggs fail to mature on a regular basis, ovulation occurs very infrequently, often at four to six month intervals, decreasing the potential to achieve a pregnancy. Since the hormonal changes that normally follow ovulation do not take place each month, women may go several months without a menstrual period. Sometimes, however, the lack of proper hormone production that normally follows ovulation can result in prolonged bleeding or spotting that can last for weeks unless treatment is provided.

Criteria for Diagnosis

The current criteria for the diagnosis of PCOS require the presence of two of the following three characteristics: (1) infrequent menstrual periods; (2) increased androgen production, usually signified by the presence of acne or increased male-pattern hair growth on the face, chest, back or abdomen; and (3) ovaries that appear polycystic on ultrasound. Some women with PCOS will have normal appearing ovaries on ultrasound. Conversely, polycystic appearing ovaries may be present in women with normal menstrual cycles. There are no laboratory tests that are diagnostic of PCOS. Rather, laboratory testing is used to rule out other causes of ovulation failure, such as elevated prolactin levels, thyroid problems, or other causes of excessive androgen production, such as ovarian or adrenal gland tumors.

Insulin Resistance/Obesity

Women with PCOS can be partially resistant to the effects of insulin in the body. Although most of these women do not have diabetes, they maintain their blood sugar in the normal range by producing a higher level of insulin than normal. This increase in insulin levels, when present, is also thought to be a cause of the increased androgen production that causes the acne, hair growth and ovulatory problems typical of women with PCOS.

Obesity, which is present in approximately 30 to 50 percent of patients with PCOS, is an independent cause of insulin resistance that may result in a more severe degree of insulin resistance in women with PCOS who are also overweight. For some women, weight loss through dietary changes and exercise can decrease insulin resistance and result in the resumption of normal ovulation.

Since the demonstration of insulin resistance requires specialized procedures, the measurement of insulin levels is not recommended. However, screening for diabetes is warranted when there are suggestive symptoms, such as excessive thirst and frequent urination.

Long-Term Risks of PCOS

Women with PCOS continue to make estrogen but since they do not ovulate their ovaries do not produce the progesterone hormone that is normally secreted after ovulation. As noted previously, this can sometimes cause prolonged uterine bleeding, which, if left untreated, can cause anemia. Continued estrogen stimulation of the uterus that is not balanced by monthly progesterone production may increase the risk of uterine cancer in women with PCOS.

Women with PCOS are also known to be at increased risk of diabetes and high blood pressure as they get older. It has been recognized that the increased androgen levels seen in PCOS can decrease HDL (good) cholesterol and slightly increase LDL (bad) cholesterol and triglycerides. Although the actual consequences of these changes are unknown, they may increase the long term risk of cardiovascular disease in women with PCOS.

Treatment of PCOS When Pregnancy is Not Desired

In women who are not currently planning to conceive, monthly periods should be induced either with birth control pills or with the monthly use of natural or synthetic progesterone. Oral contraceptives, which contain estrogen and a synthetic progesterone, will protect against uterine cancer and have the additional advantages of preventing unwanted pregnancy and suppressing testosterone production from the ovary, helping to decrease the unwanted hair growth and acne that occur in many cases. Alternatively, for women who do not require contraception, progesterone can be taken for 12 days each month to induce a period and also decrease the risk of uterine cancer.

Spironolactone (Aldactone) is a diuretic (water pill) with anti-androgen properties that has also been used to treat the excessive hair growth and acne seen with PCOS. The use of spironolactone alone may result in spontaneous ovulation and should be used along with a method of contraception. Many women treat the increased hair growth by simple mechanical measures such as shaving, plucking and bleaching or by the use of electrolysis or laser therapy.

Metformin (Glucophage) is an insulin sensitizing drug that has been used for many years to treat diabetes and has also found use in the treatment of PCOS. By decreasing insulin levels, the use of Metformin may result in ovulation and an improvement in cholesterol and triglyceride levels. Metformin is available as a pill that is taken two to three times daily. Its major side effect is intestinal discomfort and diarrhea, which may lead some women to discontinue its use within a short period of time.

Ovulation Induction to Achieve Pregnancy

Women who wish to become pregnant will require medication that will stimulate the ovulation process. There are several drugs available, including Clomid, which is the most commonly used medication with the longest track record, Metformin, which will stimulate ovulation for some women but appears to be less effective than Clomid, and a group of drugs known as gonadotropins (Bravelle, Menopur, Gonal-F, Follistim), which are used as second-line treatment when Clomid has been ineffective. All of these drugs are more fully described in the section on infertility drug treatment.

Laparoscopic Ovarian Drilling

It has been shown that cauterizing the surface cysts on the ovaries in women with PCOS can change the hormonal environment in such a way as to allow for spontaneous ovulation without the use of medication. This procedure can be accomplished as outpatient surgery through the laparoscope. However, the healing process does have the potential to cause scar tissue to form around the ovaries, which can prevent the eggs from escaping into the fallopian tubes to be fertilized with sperm. For this reason, ovarian drilling is generally recommended only in cases where drugs have not been effective or there are financial or other considerations that prevent their use. Pregnancy rates of up to 60 percent have been reported following laparoscopic ovarian drilling. 

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