Objective — to optimize the diagnosis of impaired endometrial receptivity. Subject and methods. A prospective comparative controlled study was conducted in 210 patients, including 182 patients with endometrial hypoplasia clinically manifested as infertility, miscarriage, and unsuccessful attempts at using assisted reproductive technologies and 28 apparently healthy fertile patients with a history of term labor that ended in the birth of healthy babies. The investigators comparatively analyzed the data of the patients’ history, pelvic ultrasound examination, morphological and immunohistochemical analysis of the endometrial samples taken on the day of the putative window of implantation on day 7 after ovulation determined according to the data of a urinary test and the results of office hysteroscopy. Results. The authors developed the system for diagnostic procedures, which provides an assessment of the informative ultrasonic and morphofunctional characteristics and state of the endometrial microbiota, diagnostic hysteroscopy and determination of endometrial receptivity using the created prognostic model, which makes it possible to diagnose endometrial receptivity disorders with an accuracy of 92.5% and to detail their cause.