ABO and endometriosis: Therefore, to fill in this information gap, in this study, our primary Aim was to determine whether the distribution of ABO and Rh blood groups is associated with the incidence of endometriosis among women who presented to King Abdulaziz University Hospital (KAUH) Obstetrics and Gynecology Clinic, Jeddah, Saudi Arabia, and also evaluate the potential risk factors related to endometriosis among the population.