Polycystic ovarian syndrome (PCOS) is characterized by persistent anovulation that can lead to clinical manifestations, including enlarged polycystic ovaries, secondary amenorrhea or oligomenorrhea, obesity, hirsutism, and infertility. The syndrome has a prevalence of 5–10%, with variance among races and ethnicities. Approximately 50% of patients are hirsute, and 30–75% are obese. A presumptive diagnosis of PCOS often can be made based on the history and initial examination. According to an international consensus group, the syndrome can be diagnosed if at least 2 of the following conditions are present: oligomenorrhea or amenorrhea, hyperandrogenism, and polycystic ovaries on ultrasound. Polycystic ovaries have been called “oyster ovaries” because they are enlarged and “sclerocystic” with smooth, pearl-white surfaces without indentations. Many small, fluid-filled follicle cysts lie beneath the thickened fibrous surface cortex (Fig. 41–4). Luteinization of the theca interna is usually observed, and occasionally focal stromal luteinization is seen. Laboratory testing often reveals mildly elevated serum androgen levels, an increased ratio of luteinizing hormone to follicle-stimulating hormone (LH/FSH), lipid abnormalities, and insulin resistance. Anovulation is identified in women with persistently high concentrations of LH and low concentrations of FSH, a low day-21 progesterone level, or on sonographic follicular monitoring. PCOS is presumably related to hypothalamic pituitary dysfunction and insulin resistance. A primary ovarian contribution to the problem has not been clearly defined.
Most patients with PCOS seek treatment for either hirsutism or infertility. The hirsutism can be treated with any agent that lowers androgen levels, and OCPs are typically the first choice in patients not desiring pregnancy. Infertility in PCOS patients is often responsive to clomiphene citrate. In the recalcitrant case, the experienced clinician can add human menopausal gonadotropin to produce the desired ovulation. Recent studies indicate that therapy with metformin improves fertility rates both when given alone and, even more so, when given in conjunction with clomiphene. Studies show that a small reduction in body weight, as little as 2–7%, is associated with improved ovulatory function in women with PCOS. As patients with PCOS are chronically anovulatory, the endometrium is stimulated by estrogen alone. Thus endometrial hyperplasia, both typical and atypical, and endometrial carcinoma are more frequent in patients with PCOS and long-term anovulation. Many of these markedly atypical endometrial features can be reversed by large doses of progestational agents, such as megestrol acetate 40–60 mg/d for 3–4 months. Follow-up endometrial biopsy is mandatory to determine endometrial response and subsequent recurrence.