Like many girls, Robin M. was 14 years old when she first got her period. Over time, she discovered that it came only once or twice a year; she never knew when it would happen. Her family and her doctors chalked it up to Robin's athleticism -- she was a swimmer, a dancer, and a sprinter on her high-school track team.

But once Robin reached her twenties, she knew that sports alone could no longer explain her reproductive health problems. By 1998, in her thirties and engaged to be married, Robin still menstruated only twice a year, and she had become concerned about being able to have children. Years of visits to gynecologists had offered nothing but prescriptions for birth control pills. It wasn't until she visited an Internet support group on infertility that Robin stumbled on a description of symptoms that sounded just like her own. Soon afterward she saw a reproductive endocrinologist who confirmed it: She had multiple cysts on her ovaries, part of a condition called polycystic ovarian syndrome (PCOS).

Though many women have never heard of it, PCOS is a leading cause of infertility and the most common endocrine disorder among women. It affects an estimated 5 to 7 percent of women of reproductive age -- up to an astonishing five million women in the United States. The hallmarks of the syndrome are irregular or absent menstrual periods, multiple pearl-like cysts on the ovaries (visible on a sonogram), and high levels of androgens, or male hormones, which sometimes result in excessive body- and facial-hair growth, adult acne, or male-pattern balding.

First identified as Stein-Leventhal syndrome in the 1930s, PCOS was long considered either a rare fertility problem or a cosmetic issue, and was often missed, misdiagnosed, or ignored by physicians. Researchers now know that the syndrome is in fact a metabolic disorder, affecting the entire body and placing women at greatly increased risk for life-threatening illnesses such as diabetes, coronary heart disease, and endometrial cancer.

An important key to understanding PCOS is the hormone insulin. A majority of women with PCOS -- probably 80 percent -- produce too much insulin, due to a prediabetic condition called insulin resistance. Women with insulin resistance often crave carbohydrates, have difficulty keeping weight off, and are prone to elevated cholesterol, high blood pressure, and lipid abnormalities -- all of which increase the risk of diabetes and coronary heart disease. In addition, excess insulin spurs the ovaries to produce high levels of male hormones, causing the missed periods, excessive hair growth, and acne that are often symptoms of PCOS.

Symptoms of PCOS differ widely from one patient to the next. Some women deal from puberty onward with what many patients call "crippling" obesity, acne, and excessive hair growth. Other women have mild, barely visible symptoms but have always had irregular periods. Still others see milder symptoms worsen when weight gain or stress brings on the full-blown syndrome, often when they are in their twenties or thirties.

From puberty on, Susannah L. was overweight and had irregular periods and hair growth on her chin. "I thought it was just one of those things that you had to deal with, being a woman," she says. Doctors say they hear this reaction all the time. "There are so many women who think that the excessive body hair is something they just got from their family, or they think some people just have irregular menstrual cycles," says Daniel Stein, M.D., of the Division of Reproductive Endocrinology at St. Luke's-Roosevelt Hospital Center, in New York City. "And it's so much more than that."

Susannah was 25 when she was diagnosed; Robin was 34. Because they weren't diagnosed earlier, these women sustained 10 to 20 years of metabolic damage as a result of PCOS. But the last few years have brought breakthroughs in the diagnosis and treatment of PCOS, and in patient awareness. Two advocacy groups -- the Polycystic Ovarian Syndrome Association (PCOSA) and the PCOS support group of the American Infertility Association (AIA) -- have made it possible for women to learn about PCOS, find the right doctors, and receive prompt diagnosis and appropriate treatment. When Danielle M.'s persistent menstrual problems worsened her freshman year in college, two different gynecologists diagnosed her with PCOS. Both doctors prescribed birth control pills that didn't work for Danielle. Through PCOSA, Danielle's mother found an endocrinologist who put Danielle on insulin-sensitizing medication immediately. The difference, says Danielle, was like "night and day."

According to Beth Kushnick, who heads the PCOS support group of the AIA and chaired a lay conference on PCOS last October, there is no reason for doctors to misdiagnose PCOS today. "This is not a mysterious syndrome to test for," says Kushnick. She stresses that the key is to find a "PCOS-friendly" physician, someone who is aware of and interested in the syndrome and has experience in treating it. Because PCOS is a metabolic disorder, patients are encouraged to see an endocrinologist, though well-trained internists or gynecologists can also treat the syndrome. More important than specialty, Dr. Stein believes, is interest. "PCOS is a disorder that takes time and energy to treat," he says. "You have to have a practitioner who wants to give the time and is going to consider all the issues."

Because of the link to insulin resistance, PCOS can now be treated effectively, usually with a combination of exercise, a low-carbohydrate diet, and insulin-sensitizing medications typically used for diabetes. A new insulin-sensitizing drug, D-chiro-inositol (also called INS-1), was designed specifically for PCOS and Type II diabetes and is now in clinical trials. When it comes to getting pregnant, Kushnick and Dr. Stein agree that women with PCOS need specialized fertility treatment because they have an increased risk of problems such as ovarian hyperstimulation and miscarriage.

Like Robin, many women now begin to suspect that they have PCOS when they recognize their own symptoms in a magazine article or on a website. With the increased media attention, says Kushnick, "hundreds of women are saying to me, 'I read that article; that was me.' " But for too many women, PCOS is still what researchers call a "silent syndrome."

If you have PCOS, or suspect that you do, consider taking these steps:

1. Educate yourself. There is a wealth of information available about PCOS, and the websites for both the AIA and PCOSA (addresses listed below) are the best places to start. "Go into your doctor's office with a list of questions, or print out an article from the Web," says Susannah, "and say, 'This is what's concerning me.' " If you're the parent of a teenage girl with irregular periods, don't dismiss the problem: Have her examined for PCOS.

2. See the right doctor, and get the right tests. If you trust your primary-care physician (PCP) or gynecologist, says Kushnick, start there. But if that person fails to address your concerns, find a PCOS-friendly physician who will. (The AIA or PCOSA can help direct you to these practitioners.) Insist on being referred to an endocrinologist if a PCP or gynecologist can't help you; and if you're trying to get pregnant, go directly to a reproductive endocrinologist. Dr. Stein explains that no matter whom you see, a PCOS diagnosis should be based on three things: clinical evaluation (observing your symptoms), blood tests to check hormone levels, and a vaginal ultrasound to look for polycystic ovaries.

3. Get long-term care. A doctor who treats PCOS merely as a fertility or cosmetic problem is not offering you adequate health care. Susannah's gynecologist, who diagnosed her as having PCOS, simply told Susannah she would have to take hormones if she wanted to get pregnant. And when Kushnick was diagnosed at age 14, her doctor told her, "You'll be fine when you go through menopause." Dr. Rogerio Lobo, professor and chairman of obstetrics and gynecology at Columbia University, explains that "PCOS is really a metabolic syndrome. Whether they're interested in fertility or not, women with PCOS need to be followed fairly carefully just to make sure they don't develop some of the later consequences."

4. Change your lifestyle. Because insulin resistance plays such an important role in PCOS, says Dr. Lobo, "the first line of treatment is diet and exercise." And since insulin-resistant women have difficulty losing weight, Dr. Stein says, "patients can't just be told to lose weight; they need help to do that." Doctors and PCOS advocates agree that a low-carbohydrate diet is often very helpful. "When you have PCOS and you eat carbohydrates," says Kushnick, "you're adding fuel to the fire."

5. Get to know your family history. Researchers agree that there is a strong genetic component to PCOS. Find out if any of your female relatives have symptoms like irregular periods, abnormal hair growth, and infertility, and ask about any family history of adult-onset diabetes.

6. Get support. Joining a local chapter of the AIA or PCOSA can make an enormous difference. "Women can give other women hope, alleviate fear, give them support, and also point them in the right direction for care," says Pamela Madsen, executive director of the AIA. Susannah agrees. "Find out about yourself, and talk to other women," she says. "That's helped me more than anything."

SIDEBAR: Medications Used to Treat PCOS

For more information on PCOS, contact the following organizations:

(AIA), 666 Fifth Avenue, Suite 278, New York, NY 10103; (888) 917-3777

(PCOSA), P.O. Box 7007, Rosemont, IL 60018-7007; (877) 775-7267

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