Medical errors resulting in dangerous treatment can come from many directions. A prescription may be filled incorrectly. A test result may be misread. And sometimes, the very definition of a condition is outright wrong. Such may be the case with polycystic ovary syndrome, a disorder diagnosed in millions of women every year—many of them incorrectly, researchers say.

Polycystic ovary syndrome, or PCOS, is a common hormonal disorder that causes acne and difficulty gettting pregnant, among other problems.

In a new editorial, Australian researchers argue that women around the world are being overdiagnosed with PCOS because medical authorities changed the definition of the syndrome.

Those at risk of being overdiagnosed, the authors say, include adolescents and young women. The excess diagnoses are a problem because the condition is deeply stigmatized, possibly due to the pyschological effect of being labelled as having PCOS.

The National Institutes of Health (NIH) first recognized PCOS more than eight decades ago. Since then, its definition has undergone several revisions. In 1990, diagnostic criteria were established for PCOS. Then, in 2003, the criteria were expanded to include the presence of polycystic ovaries identified via ultrasound, leading many experts to argue that the new definition resulted in overdiagnosis or misdiagnosis of PCOS.

But now, the current definition for PCOS doesn't even require having cysts. A diagnosis requires having at least two of the following criteria: high levels of male sex hormones; menstrual period changes; and/or multiple cysts on one or both ovaries, according to the American Association of Clinical Endocrinologists.

These criteria present a challenge for medical experts diagnosing PCOS in young adults, Tessa Copp, leading author, argues. “Many symptoms of PCOS, such as acne and oligomenorrhea, overlap with features common to pubertal development, but diagnostic criteria for PCOS don’t take adolescence into account,” she said in a statement.

The name also contributes to the confusion. In 2013, an NIH panel suggested PCOS be renamed because women who have the disorder don’t always have cysts and if they do have cysts, they must meet other criteria.

“The name PCOS is a distraction that impedes progress. It is time to assign a name that reflects the complex interactions that characterize the syndrome,” Dr. Robert A. Rozza, professor of medicine at the Mayo Clinic, said in a statement. “The right name will enhance recognition of this issue and assists in expanding research support.”

Avoiding incorrect diagnoses will likely require better discussions at the clinic. “Women need more transparent clinical conversations with their doctor so they understand the limits of current evidence and the impacts of applying one-size-fits-all diagnostic criteria to an often wide-ranging set of presenting symptoms,” Copp, of the University of Sydney, said in the statement.

Copp also cautions about rushing the diagnosis of PCOS. Young adults with less severe symptoms may see improvement over time, making treatment unnecessary. “Although some women, such as those with ‘classic’ NIH phenotypes or those with more severe symptoms, may benefit from PCOS diagnosis,” says Copp, “other women may not need this label to effectively and rapidly treat their presenting symptoms.” And more research is needed to clearly determine the benefits and risks of treating women with various types of the stigmatized disorder, says Copp. Those at risk of overdiagnosis should be treated symptomatically instead of by a textbook definition.

Despite this problem, women with PCOS symptoms should pay attention to them because not seeking medical attention can also pose serious risk. Catching PCOS early may help reduce the risk of long-term complications such as type 2 diabetes, according to Mayo Clinic.