The reported number of cesarean sections in Poland is approximately 30% and is associated with increasing number of early and late complications. The myometrial discontinuity at the site of previous cesarean section is known in the literature as "isthmocoele", "niche", "pouch" or cesarean scar defect. In most cases presence of isthmocoele has no clinical significance, but in some patients it may cause abnormal uterine bleeding, dysmenorrhea, dyspareunia, pelvic pain or be associated with secondary infertility. This defect may be treated by laparoscopy, hysteroscopy or vaginal surgery.