It took journalist Lizzie OLeary 21 years to be diagnosed with endometriosis, even though her symptoms appeared shortly after her first period. An entire person could have grown up and legally bought alcohol in the time it took for me to get diagnosed, OLeary explained.

Shes not alone. According to the Endometriosis Foundation of America , at least 200 million women worldwide have endometriosis, an estrogen-dependent chronic inflammatory disease that affects women starting at reproductive age. Tissue similar to the uterine lining grows outside of the uterus, causing painful lesions. According to Dr. Tamer Seckin, a prominent gynecological surgeon who operated on Lena Dunhams endometriosis , the symptoms can vary widely, but among the most common are severe pelvic pain, loss of quality of life, and sub-fertility.

On average, women suffer with symptoms for 10 years before receiving a correct diagnosis. And even with diagnosis, the pain can continue, since there is no cure for the condition. Dr. Seckin noted that the most common treatments are hormones and the surgical removal of the lesions.