The endometrium is where the embryo is laid and grows and develops, but in pathological states, such as endometritis, endometriosis and adenomyosis, the endometrium can be transformed into an antigen or semi-antigen, stimulating the body to produce the corresponding antibodies itself. Anti-endometrial antibodies are autoantibodies that use the endometrium as the target antigen and cause a series of immune responses. When combined, the antigen-antibodies can be deposited in the endometrium and ectopic lesions, and destroy the structure of the endometrium by activating complement. It has been reported that the positive rate of anti-endometrial antibodies in blood is significantly higher in women with endometriosis and infertility than in normal controls, with the detection rate of anti-endometrial antibodies in endometriosis serum reaching 70%-80%. Clinical studies have shown that ectopic endometrium is antigenic and can induce the body to produce endometrial antibodies, and the presence of endometrial antibodies in women can lead to infertility, pregnancy cessation or miscarriage.