What is polycystic ovary syndrome?
Polycystic ovary syndrome (PCOS) seems to be caused by a combination of genetics and environmental factors. Researchers are currently using candidate gene research to try to determine which genetic sequences may lead to susceptibility for PCOS. First-degree relatives of someone with PCOS are at higher risk of developing the condition themselves. Exposure to prenatal androgens may play a role, although this exposure may occur anywhere from the prenatal period through puberty. Additionally, in the prenatal period, the androgens appear to be from the fetus and not the mother.
Hyperinsulinemia and obesity both contribute to higher levels of androgens, called hyperandrogenism. Insulin may directly stimulate the production of androgens from the ovary, or it may indirectly affect androgen levels by inhibiting sex hormone-binding globulins. Obesity is associated with hyperinsulinemia.
The signs and symptoms can be ambiguous. The most common are related to the hyperandrogenism and include hirsutism (excess facial hair), infertility, and menstrual irregularities. Acne and male-pattern baldness may also occur. The 1990 National Institutes of Health classification of PCOS requires disordered ovulation and clinical or biochemical evidence of hyperandrogenism. In 2003, the Rotterdam European Society of Human Reproduction and Embryology/American Society of Reproductive Medicine consensus workshop included having polycystic ovaries but suggested that two of these three symptoms were enough on which to base a diagnosis. Thus, a woman with PCOS may have disordered ovulation and polycystic ovaries with androgen excess, or androgen excess with polycystic ovaries but no disorder in ovulation. However, other scenarios are possible.
Hyperandrogenism can be evaluated through laboratory tests, including testosterone levels, sex hormone-binding globulins, and other androgen levels. However, these tests have not always reliably reflected PCOS symptoms. Ultrasound is used to detect the presence of polycystic ovaries and may include an assessment of follicle number and ovary size. Criteria for ultrasound evaluation include having twelve or more follicles that are two to nine millimeters in diameter or ovarian volume greater than ten cubic centimeters.
The main goal of treatment and therapy is to normalize menstrual cycles and ovulation and, if desired, achieve a successful pregnancy. The least-invasive approach to achieving this goal is weight loss in those who are overweight. Weight loss of 5 to 10 percent has been shown to have a positive impact on symptoms of PCOS—hirsutism, infertility, and menstrual irregularities as well as hyperinsulinemia. This goal can be achieved by a reduction in caloric intake and increased physical activity, although it is difficult to maintain.
Although weight loss is helpful, it may not alleviate all symptoms of PCOS in overweight females. In addition, only about half of those with PCOS are estimated to be overweight. Medications may be prescribed to achieve menstrual regularity or normalize blood glucose levels. Birth control medications will help to regulate menses if the woman is not trying to conceive. However, they may also result in weight gain and insulin resistance, which would be a negative effect for the PCOS treatment overall. Clomiphene citrate, a selective estrogen receptor modulator (SERM), may be prescribed to enhance the chances of conception, if this is desired. However, only 35 to 40 percent of women receiving this medication become pregnant. If clomiphene citrate fails to induce conception, then exogenous gonadotropins or laparoscopic ovarian surgery may be tried. However, gonadotropin therapy is associated with multifetus pregnancy, which is not found as often with surgery. However, regimens with low doses of gonadotropins have had some success over traditional doses in achieving single pregnancy. If these options fail to produce pregnancy, then in vitro fertilization is also an option.
For blood glucose normalization, oral hypoglycemic agents such as the biguanide metformin are usually prescribed. Some studies have suggested this medication may also enhance fertility, although other studies have found no such result. Current recommendations are to discontinue metformin when pregnancy is confirmed. Some suggest that metformin may be continued through pregnancy if type 2 diabetes is present. Nonsteroidal antiandrogen medications may help improve the symptoms of androgen excess, although they are not commonly used in adolescents. While several medications may improve hirsutism to some extent, nonpharmacological treatment can also be used, including waxing, electrolysis, bleaching, plucking, and heat or laser therapy.
First described by Irving F. Stein and Michael L. Leventhal in 1935, PCOS was for a time referred to as the Stein-Leventhal syndrome. At that time, surgical resection of the ovaries was fairly successful treatment, although complications with internal adhesions eventually made other treatments more desirable.
The prevalence of PCOS has been estimated from 2 to 30 percent of premenopausal women. While women of childbearing age were at one time believed to be the primary group afflicted with PCOS, adolescents are now also being diagnosed with the disorder. The diagnosis is somewhat more difficult because menses are often irregular until at least two years past menarche.
Polycystic ovaries by themselves have no long-term negative effects, although women with polycystic ovaries without the symptoms of the syndrome are at higher risk for hyperstimulation syndrome. Those with PCOS are at higher risk of complications associated with diabetes and cardiovascular disease. Depression and a reduced quality of life have been reported in women with PCOS, possibly as a result of difficulties with conception, dissatisfaction with appearance, and issues associated with chronic disease.
Dunaif, Andrea, et al., eds. Polycystic Ovary Syndrome: Current Controversies, from the Ovary to the Pancreas. Totowa, N.J.: Humana Press, 2008.
Franks, Stephen. “Polycystic Ovary Syndrome.” Medicine 37, no. 9 (September, 2009): 441–444.
Hoeger, Kathleen M. “Role of Lifestyle Modification in the Management of Polycystic Ovary Syndrome.” Best Practice and Research: Clinical Endocrinology and Metabolism 20, no. 2 (June, 2006): 293–310.
MedlinePlus. "Polycystic Ovary Syndrome." MedlinePlus, May 13, 2012.
Norman, Robert J., et al. “Polycystic Ovary Syndrome.” The Lancet 370, no. 9588 (August 25, 2007): 685–697.
Radosh, Lee. “Drug Treatments for Polycystic Ovary Syndrome.” American Family Physician 79, no. 671 (April 15, 2009): 671–676.