What Is PCOS, Exactly?

This informational guide, part of POPSUGAR's Condition Center, lays out the realities of this health concern: what it is, what it can look like, and strategies that medical experts say are proven to help. You should always consult your doctor regarding matters pertaining to your health and before starting any course of medical treatment.

Editor's note: We at POPSUGAR recognize that people of many genders and identities have uteruses — not just women. For this particular story, the expert and studies we relied on generally referred to people with vaginas and uteruses as women.

Irregular periods aren't necessarily a cause for concern. But if you have fewer than nine periods a year, more than 35 days between periods, or extremely heavy periods, it could be a sign of polycystic ovary syndrome, or PCOS. "There are health risks associated with the condition, including infertility and diabetes, so it's important to talk to your doctor if you have symptoms," says Paula Amato, MD, a reproductive endocrinologist and professor of obstetrics and gynecology at Oregon Health & Science University in Portland. Here's what you need to know about this common condition.

PCOS is a hormonal disorder that affects up to 12 percent of people who have vaginas and uteruses and are of reproductive age, according to the Centers For Disease Control and Prevention. The condition causes the body to produce higher-than-usual amounts of androgen (a sex hormone), which can cause acne, excess facial- and body-hair growth, and weight gain in addition to irregular periods, Dr. Amato says.

The condition can also affect the ovaries' ability to release eggs and is thought to be responsible for 80 percent of instances of anovulatory infertility, which refers to infertility caused by a lack of ovulation (this makes up about 25 percent of all infertility cases).

"It also can cause metabolic complications, which raise the risk for diabetes and sleep apnea and possibly heart disease," Dr. Amato says. More than half of people with PCOS develop type 2 diabetes by age 40, according to the CDC.

The other big risk associated with PCOS is uterine cancer, Dr. Amato says. "When you have irregular cycles, the uterine lining is at risk for overgrowth, which, unchecked, can lead to cancer," she explains. "Early diagnosis is important, because the earlier you catch PCOS, the easier it is to prevent long-term health problems."

While experts don't know exactly what causes the condition, there are some hallmarks of the syndrome that could play a role in its development or may be responsible for its main symptoms.

"Treatments vary and are geared toward the needs and goals of each patient," Dr. Amato says. Many people with PCOS first try taking birth-control pills, which both regulate periods and reduce androgen levels to improve symptoms like acne and facial and body hair. People trying to get pregnant may be prescribed medication to induce ovulation. Doctors sometimes also prescribe diabetes medications, which can increase the body's response to insulin and treat insulin resistance (and type 2 diabetes) and may also reduce androgen levels and help restore normal ovulation.

"In addition, many women with PCOS will benefit from lifestyle changes, like improving their diet and getting more physical activity," Dr. Amato says. Treating weight gain, when it's a symptom, may help improve insulin sensitivity, lower blood-sugar levels, and increase the likelihood of ovulation. That said, emerging research indicates that people with PCOS may be at an increased risk of developing eating disorders, so it's important to take a person's entire health into account, rather than focusing on a number on the scale. "PCOS isn't curable," Dr. Amato notes, "but you can manage the symptoms so it doesn't adversely affect your health."