Oxidative stress is manifested with abundant ROS and deficient antioxidant mechanisms because of an imbalance between ROS and antioxidants (SOD, CAT, and GSH), which is crucial in the pathophysiology underlying EMs and also plays a role in endometriotic pain.31,32 In our study, ELISA results revealed that the contents of ROS and MDA increased and the activities of SOD, CAT, and GSH decreased in rats with EMs, further confirming the implication of oxidative stress in the progression of EMs. This evidence concerns the gene CAT and eosinophilia-myalgia syndrome.