In some women with a history of CS it is possible to recognise a defect in the site of previous uterotomy years after the performed CS by sonographic examination. This defect in the scar, also called as a niche, is a consequence of incomplete healing of the scar in the lower part of uterus. To date there is uncertainty relating to the factors that lead to poor healing of cesarean scar. Also impact of cesarean scar defect on later well-being and later pregnancies are not properly known.