Endometritis is a common gynecological disease in clinical practice. There are many causes of endometritis, which can lead to inflammatory changes in the endometrial structure. Bacteria can ascend from the vagina and cervix, descend from the fallopian tubes, or reach the endometrium through the lymphatic system, causing the disease. For example, childbirth and the weakened immune response afterward can lead to pathogen invasion if the placenta and membranes are retained. The placental separation surface can be infected by bacteria causing inflammation of the endometrium. Additionally, the placement or removal of an intrauterine device, abortion procedures, dilation and curettage, and medication-induced abortion can also facilitate the invasion of pathogens and trigger endometrial inflammation.