Background
Polycystic ovarian syndrome (PCOS) is the most common condition among reproductive‐aged women. However, its exact prevalence is unknown.

Aims
To determine the prevalence of PCOS in Australian women aged 16–29 years using the National Institutes of Health (NIH) criteria compared to self‐reported PCOS, to compare co‐morbidities between the groups and to determine the most distressing aspect of a diagnosis of PCOS for these young women.

Materials and Methods
Participants were recruited from the Young Female Health Initiative (YFHI) and Safe‐D studies. Participants completed questionnaires, physical examinations and blood tests from 2012 to 2016. In March 2016, two supplementary questionnaires were distributed: the first, comprising questions on reproductive health and impact of diagnosis, was sent to participants who self‐reported having PCOS in the original studies. The second, comprising general reproductive health questions, was sent to the remainder.

Results
The prevalence of PCOS, according to the NIH criteria, was 12% (31/254), while the prevalence of self‐reported PCOS was 8% (23/300). Only 35% (8/23) of those with self‐reported PCOS actually fulfilled the NIH criteria for PCOS. Comorbidities were relatively similar among groups. Finally, approximately 65% (15/23) were unhappy or worried about their initial PCOS diagnosis, with 72% (13/18) stating fertility concerns were the most distressing aspect of their diagnosis.

Conclusions
The lack of consistent and accurate diagnosis of PCOS in young women potentially leads to over‐diagnosis. This creates unnecessary fears of health complications, particularly infertility. Therefore, we recommend the development of standardised criteria with set parameters that allow for better diagnosis of PCOS.