Endometriosis is a chronic inflammatory disease that is found in 10% of post-pubertal women, but up to 35-50% of individuals presenting with infertility and pelvic pain.1 In adolescents with pain refractory to medical management, endometriosis is present in 50-75% those undergoing laparoscopy. Typically, endometriosis presents after menarche with cyclic and acyclic pain. However, there is a case series of endometriosis in premenarchal patients.2

We present a unique case of endometriosis in a pre-pubertal patient with 46,XY difference of sex development (DSD). This case highlights the complex, poorly understood, and multifactorial origins of endometriosis.