Polycystic Ovary Syndrome


Polycystic ovary syndrome, otherwise known as PCOS, is caused by a hormone imbalance that interferes with normal ovulation. Hirsutism, acne or androgenic alopecia are conditions that can be the result of increased production of male hormone, called androgens, in women with PCOS.

The name polycystic ovary syndrome is derived from the cystic appearance of the ovaries of affected women.  Also referred to as the Stein-Leventhal syndrome, Polycystic is a term that simply means "many cysts." The polycystic ovary typically contains many small - usually less than 1 centimeter - cysts (fluid-filled sacs). These cysts are usually arranged around the surface or just below the surface layer of the ovary. When examined directly or by ultrasound, these small cysts commonly are said to have a string-of-pearls appearance. The ovaries of affected women can be slightly enlarged when compared to unaffected ovaries.

Each of these small cysts represents a follicle, which contains a single egg that is attempting to develop to a stage where it will be ready to be released from the ovary (a process known as ovulation). However, because of the complex biochemical situation that exists in ovaries with PCOS, the development of these follicles stops too soon, resulting in a collection of small follicles and the lack of ovulation. This lack of ovulation is the reason why women with PCOS commonly have difficulty becoming pregnant.

PCOS may increase your risk of developing other conditions or diseases over time, such as diabetes, high cholesterol, heart disease and endometrial hyperplasia.


PCOS symptoms vary widely and are similar to symptoms for other conditions. Therefore, women with these symptoms do not necessarily have PCOS.

Symptoms include:

  • Excess hair growth (hirsutism), acne or balding
  • Infertility
  • Irregular ovulation and abnormal menstrual periods
  • Obesity and insulin resistance
  • Polycystic ovaries

Excess Hair Growth, Acne or Balding

Women affected by PCOS commonly report bothersome excess hair growth, acne or balding (scalp hair loss or thinning). Hirsutism refers to the excess growth of coarse, often long and dark hair, in a male-like pattern over the face, chest, abdomen, back, arms and legs. Balding, also called androgenic alopecia refers to the loss or thinning of scalp hair.

Hirsutism, acne or androgenic alopecia can be the result of increased production of male hormone, called androgens, in women with PCOS. The ovaries, and frequently the adrenals of women with PCOS overproduce androgens. The excess male hormones circulate in the blood and act on hair follicles in the skin to stimulate the growth of long, coarse and commonly dark hairs. They also cause hairs in the scalp to stop growing, resulting in balding. Excess androgens also result in the overproduction of sebum, the skin oil, which results in clogged pores and acne.

In addition to being considered a significant cosmetic problem for many women, hirsutism, acne and androgenic alopecia may indicate an underlying problem of significant concern - elevated androgen levels. There is evidence to suggest that long-standing elevations in androgens in women with PCOS can lead to problems with cholesterol and other lipid levels, which are risk factors for heart disease.

It is important to note that not all women with hirsutism, acne or alopecia have PCOS. Also, not all women with hirsutism will be found to have elevated androgen levels. Conversely, not all women with PCOS will have hirsutism.

An important factor in the development or lack of development of hirsutism is race and ethnicity. It has been shown that women of eastern European decent are at increased risk of demonstrating hirsutism, whereas Asian women will have little or no hair growth, despite similar levels of androgens.


Women with PCOS often experience difficulty becoming pregnant. In PCOS both ovulation (release of an egg from the ovary) and the development of the endometrium are abnormal. Normal fertility requires that the ovary release an egg or ovum, which can be fertilized by the male sperm. After fertilization, the developing embryo must enter the uterus where the endometrium is appropriately developed to allow for the pregnancy to continue.

Women with PCOS do not ovulate in a normal fashion, and as a result their endometrium is not properly developed. It is important to remember that not all infertile women have PCOS. There are many causes of infertility, of which PCOS is only one.

It is also important to remember that women with PCOS can become pregnant, in some cases naturally and in other cases with the help of medications or assisted reproductive technologies. Just because a woman has PCOS does not mean that she cannot become pregnant on her own.

Irregular Ovulation and Abnormal Menstrual Periods

One of the hallmark signs of PCOS is irregular periods. Women with PCOS commonly have periods that are much further apart than the standard 28 days. It is not uncommon for these women to go several months between menstrual periods, or even have no periods at all.

When menstrual periods are widely separated, it is called oligomenorrhea. When a woman goes six months without a period it is called amenorrhea.

In order to understand what causes women with PCOS to have irregular periods we need to establish the association between the ovary and the uterus. The ovary produces the hormones (estrogen and progesterone) which are responsible for developing the inside lining of the uterus - called the endometrium. It is the job of the endometrium to respond to these hormones in a fashion that will allow for a pregnancy to develop within the uterus if fertilization of an egg occurs. In order for the endometrium to respond correctly to the ovarian hormones the ovary must produce these hormones in a very organized fashion. The very important process of ovulation maintains this organization.

The ovaries of women with PCOS do not ovulate (release an egg) on a regular basis. Therefore, the hormones produced by these ovaries are not made in the organized fashion that the endometrium requires. The result of this disorganized hormone production is seen by the woman with PCOS as irregular menstrual periods. Commonly, when the woman with PCOS has a rare period they can be very heavy.

It is important to understand that not all women with irregular periods have PCOS. There are MANY causes for irregular periods, and women with irregular menstrual periods should be evaluated by a physician to determine the cause. It also important to remember that not all women with irregular ovulation have PCOS, and not all patients with PCOS have irregular periods. Many women who think they have "regular" menstrual bleeding or periods actually are not ovulating regularly. Hence, a close evaluation of the patients ovulation should be done in women who think they have "regular cycles" but have other signs of PCOS, such as hirsutism.

Obesity and Insulin Resistance

Many women with polycystic ovary syndrome (PCOS) are overweight, although about one-third to one-half of women with PCOS are of normal weight. Thus, women who are not obese can also have PCOS.

Many women with PCOS have some degree of insulin resistance. Insulin is a hormone produced by the pancreas that is responsible for processing the sugars (i.e., carbohydrates) that we ingest in our diets. Insulin resistance is a condition in which the tissues of the body do not respond appropriately to normal levels of insulin. This forces the pancreas to produce increasing amounts of insulin to process the same amount of sugars. As the insulin resistance becomes worse, the pancreas is forced to produce ever-increasing amounts of insulin. If the insulin resistance becomes so severe that the pancreas is not able to produce enough insulin to meet the body's needs then the patient develops diabetes mellitus.

An example of acanthosis nigricans.

Insulin resistance in PCOS is made worse by being overweight or obese. A sign of insulin resistance is acanthosis nigricans, although not all insulin resistant women have acanthosis. The exact cause of insulin resistance in women with PCOS is not yet clear. A great deal of research is being directed at discovering more about insulin resistance, why it occurs and how best to treat it.

However, what is well established is that weight reduction in overweight women with PCOS will greatly improve insulin resistance. In addition to improving insulin resistance, weight reduction can also improve many of the other signs and symptoms of PCOS. For example, overweight women with PCOS and insulin resistance who lose weight can resume normal ovulation, normal menstrual periods and normal fertility.

Although scientists are still in the process of understanding the association between obesity, insulin resistance and PCOS, what is clear is that there appears to be some common link that ties all these factors together. It is important to understand that not all obese women are affected by PCOS. Conversely, not all women with PCOS are overweight. It is also important to note that there appears to be an association between having PCOS, being overweight and an increased risk of developing diabetes.


PCOS has such a wide range of symptoms that no single test can be used to diagnose the syndrome. Several exams and tests to diagnose PCOS may be done, depending on your symptoms.

These include:

  • Blood tests
  • Insulin level tests
  • Medical history
  • Pelvic exam
  • Thyroid level tests
  • Transvaginal ultrasound
  • Urinalysis

If you have been diagnosed with PCOS, you will need yearly tests to determine your insulin, glucose, cholesterol and triglyceride levels. Regular testing will help reduce the risk of any long-term complications.

Keep in mind, not all women who are found to have polycystic-appearing ovaries on ultrasound have PCOS. The polycystic ovary is a structural finding of the ovary, and this single finding should not be confused with the entire syndrome. In fact, many women who show no other signs or symptoms of PCOS have been found to have polycystic-appearing ovaries on ultrasound.

Many women hear the term "polycystic ovary" and associate this with ovarian cancer. This is not the case. Polycystic ovaries are not cancer, and a diagnosis of PCOS does not mean that you have cancer. Also, having been told you have had or currently have an ovarian cyst does not mean you have PCOS. Remember, the normal ovary creates a cyst every month through the process of ovulation. The presence or history of an ovarian cyst does not make for PCOS.

In order to determine the cause of hirsutism, your doctor will obtain blood tests for different hormone levels. Your doctor may also order a pelvic ultrasound or X-rays to make certain you do not have an ovarian or adrenal tumor. The adrenal gland may also be checked by performing an adrenal stimulation test.


Since there is no specific cure for PCOS, treatment focuses on managing PCOS symptoms and preventing long-term complications.

Some therapies may include:

Drug therapy - Including birth control pills to correct irregular menstrual cycles, insulin-sensitizing medications, fertility medications, weight loss pills and acne medications.

Cosmetic therapy - which can include treatments for hair removal and for clearing up acne.

Hormone replacement therapy may be prescribed to correct the hormone imbalance associated with PCOS.

Nutritional counseling is available to treat obesity and help alleviate insulin resistance.

Surgery to remove the ovaries or uterus (bilateral salpingo-oophorectomy or hysterectomy) is an option for women with severely symptomatic PCOS who do not want future pregnancies.

To stop the progression of hirsutism, most women should first be treated with hormones, typically with common birth control pills. Once the hormone treatment has taken full effect, electrolysis can be used to permanently remove any remaining hairs. 

Facial creams, waxing and shaving are also helpful in reducing unwanted hair.

© 2000-2022 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.
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