In much the same way that a lack of testosterone can decrease a man's fertility, too many male hormones in a woman can do the same to her. With the condition known as polycystic ovarian syndrome (PCOS), a woman's ovaries produce too many androgens, male hormones that are present in every woman's body to a certain degree. When the body is flooded with androgens, ovulation can cease.
PCOS is the most common single factor in female infertility, affecting five to 10 percent of women of childbearing age [sources: National Institutes of Health, The National Women's Health Information Center]. In addition to infertility, polycystic ovarian syndrome may cause the following symptoms:
PCOS causes infertility because the hormonal imbalances interrupt ovulation -- the follicle fails to release an egg. This then prevents the body from producing the hormone progesterone, which regulates menstrual cycles, and hormones become further imbalanced.
In testing for PCOS, a doctor is likely to use a variety of tests, including a pelvic exam, vaginal ultrasound or blood tests. If the condition is diagnosed, one recommended treatment for overweight women is to lose weight. It's thought that insulin plays a role in PCOS, and a drop of just 10 percent body weight can help even out hormone levels [source: The National Women's Health Information Center]. If being overweight isn't a problem, common fertility medications may help. Success has also been seen with a particular diabetes medication, although its use in treating PCOS isn't approved by the Food and Drug Administration (FDA).