The PCOS Challenge Run/Walk events are the largest event in the U.S. dedicated to raising awareness and funds to help fight polycystic ovary syndrome (PCOS). Events benefit PCOS Challenge: The National Polycystic Ovary Syndrome Association. PCOS Challenge is the country’s leading 501(c)(3) public charity advancing the cause for women and girls with PCOS. Proceeds from the PCOS 5k event go toward PCOS research, education, advocacy, grants, and support programs, as well as increasing awareness and public support for those with the condition.