Introduction:The rate of attempted vaginal birth after previous cesarean delivery has decreased, while the success rate of such births increased. Advances in surgical techniques, the development of anesthesiology services, particularly endotracheal anesthesia, very quality postoperative care with cardiovascular, respiratory and biochemical resuscitation, significantly reduce maternal mortality and morbidity after cesarean section. Progress and development of neonatal services, and intensive care of newborns is enabled and a high survival of newborn infants. Complications after cesarean section were reduced, and the introduction of prophylaxis and therapy of powerful antibiotics, as well as materials for sewing drastically reduce all forms of puerperal infection.Goal:Goal was to establish a measurement value of the parameters that are evaluated by ultrasound.Material and methods:Each of the measured parameters was scored. The sum of points is shown in tables. Based on the sum of points was done an estimate of the scar on the uterus after previous caesarian section and make the decision whether to complete delivery naturally or repeat cesarean section. We conducted a prospective study of 108 pregnant women. Analyzed were: shape scar thickness (thickening), continuity, border scar out, echoing the structure of the lower uterine segment and scar volumeResults:The study showed that scar thickness of 3.5 mm or more, the homogeneity of the scar, scar triangular shape, qualitatively richer perfusion, and scar volume verified by 3D technique up to10 cm are attributes of the quality of the scar.Conclusion:Based on the obtained results we conclude that ultrasound evaluation of the quality of the scar has practical application in the decision on the mode of delivery in women who had previously given birth by Caesarean section.

I ntroduction: Cesarean section (Sectio Caesarea) is a surgical method for the completion of delivery. After various historical modifications of operative techniques, modern approach consists in the transverse dissection of the anterior wall of the uterus. The rate of vaginal birth after cesarean section was significantly reduced from year to year, and the rate of repeated cesarean section is increased during the past 10 years. Evaluation of scar thickness is done by ultrasound, but it is still debatable size of thick scar that would be guiding "cut-off value" for the completion of the delivery method. Goal: The aim was to examine the most accurate ultrasonic method for assessing thickness scar on the uterus after previous cesarean delivery and determine the threshold thickness of scar that would allow the completion of birth vaginally. Material and methods: Conducted is prospective study of 108 pregnant women aged 20-42 years, who had previously had a Caesarean section. Diagnostic accuracy in assessing the success of scar scale by evaluation of delivery (spontaneous or caesarean section). Measurements were carried out by 2D and 3D ultrasound machines in the 20, 38-40 week of gestation and 48 hours after birth. Results: Tests have shown that there is a statistically significant difference in the rates of specificity (0.04), sensitivity (0.05), PPV (0.01) and NPV (0.01) between 2D and 3D ultrasound. Ultrasound images of uterine muscle scar after prior cesarean section are better by 3D methods. The marginal value, "cut-off value" thick scar, which provides the possibility of vaginal birth after previous incision was 3.5 mm. Conclusion: The study showed that ultrasound measurement of 3D ultrasound thick scar on the uterus after previous cesarean section has practical application in determining the mode of delivery among pregnant women who have previously given birth by Caesarean section.