The subject of discussion is the effectiveness of sonographic examination in the diagnosis of chronic endometritis, despite the high availability of this method of research and ultrasound criteria of chronic endometritis. The validity of the ultrasound diagnosis of chronic endometritis is denied by many experts, but there is a consensus on the high prognostic detectable values of the signs for further verification of this nosology. Purpose — to determine the diagnostic value of pelvic ultrasound to assess the condition of the endometrium in women with unsuccessful attempts at ART in the history of chronic endometritis. Materials and methods. The prospective study of women with chronic endometritis and unsuccessful attempts at ART, based on MC LLC «ISIDA-IVF», for the period from 2019 to 2021. I and II groups were 110 women of childbearing age with chronic endometritis and repeated unsuccessful attempts at ART, and 40 women of reproductive age without impaired fertility, who formed a control group. Ultrasound of the pelvic organs was performed in all patients of the studied groups on days 5–7, 12–15, 22–24 of the menstrual cycle. The threshold value of static reliability is p<0.05. Results. In women with infertility on the background of chronic endometritis in history, the average thickness of the median M-echo in the periovulatory period in group I (with pre-conception preparation) was 9.1±0.08 mm, in group II (without pre-conception preparation) — 7.6±0.9 mm, in the CG — 9.3±0.1 mm and had statistically significant differences (p1,2<0.05, p1,3>0.05, p2,3<0.05). Thin endometrium was detected in patients of group I with pre-conception preparation in 16.3% and twice as often in women in group II without pre-conception preparation — 30.9% (p1,2<0.05). The inconsistency of endometriality was approximately the same in the number of patients in the 1st and 2nd group, which was seen during the day in the cohort of the control group. In case of hyperplastic chronic endometritis macrotype in both groups, polypendometry was tested, as in 2.5 times it was diagnosed in patients of the II group — 9.6% versus 3.6% in women of the I group (p1,2<0.05). The incidence of diagnosed hyperplasia endometrial in pre-existing groups is not small statistically significant differences — 1.8% and 5.4% (p1,2>0.05) apparently. In case of hypoplastic chronic endometritis macrotype, thin endometrium is 2 times and more often in the II group. Conclusions. Transvaginal echography has high specificity (96.6%), sensitivity (55.2%) and diagnostic accuracy (68.2%). Criterias for the active readiness of women to the vagina for pre-conception health improvement are updating the photographic picture of endometries with values of M-exo>7 mm; normalization of uterine hemodynamics (RI<0.9, PI<3.0). The research was carried out in accordance with the principles of the Helsinki declaration. The study protocol was approved by the Local ethics committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: ultrasound examination, assisted reproductive technologies, chronic endometritis.