Abstract. In this work, we analyzed the frequency of violations of the vaginal microbiota and the development of infectious and inflammatory complications during post-placental intrauterine contraceptive administration during abdominal delivery. Currently, the incidence of infectious and inflammatory diseases in obstetrics does not tend to decrease. In the structure of infectious and inflammatory diseases, a significant place is occupied by postoperative purulent-septic complications – endometritis, suppuration of wounds on the uterus and anterior abdominal wall after cesarean section. One of the tasks solved in the course of this study was to identify the correlation between the state of the birth canal microbiota and the development of complications when using IUDs during cesarean section.