The crucial role of chronic endometritis in the genesis of endometrial dysfunction has been currently established. The inflammatory process serves as a co-factor and leads to a decrease in the receptivity of the sex hormones of the endometrium due to impaired blood circulation of the tissue and fibrosis in the stroma of the endometrium. This article is devoted to the study of the morpho-functional state of the endometrium in women of the reproductive age with abnormal uterine bleeding, in whom endometritis was diagnosed pathomorphologically, which is important for clarifying indications for the pregravid preparation in the future. A comprehensive examination of patients with abnormal uterine bleeding includes: bacterial culture (PCR) of the cervical canal and uterine cavity, hormonal profile, ultrasound examination of the pelvic organs and a complex histological examination of the uterine biopsy at the 7–10th and 19–21st days of the menstrual cycle, followed by immunohistochemical examination with the use of antibodies to the receptors of estrogens and progesterone, glycodelin, CD138, CD4, CD8, CD20.