INFLUENCE OF THE NUMBER OF PREVIOUS CAESAREAN SECTIONS ON LOWER UTERINE SEGMENT STATE
Aleksandra Andrić, Mileva Milosavljević, Milan Stefanović and Predrag Vukomanović
Determining the lower uterine segment (LUS) state before vaginal delivery and after Caesarean section, including pregnant women with more than one Caesarean section, may be an important step towards prevention from still high maternal and neonatal morbidity and mortality that follow uterine rupture. In pregnant women with one or more previous Caesarean sections, ultrasonic measuring of thickness and estimating the LUS integrity can objectively show the state of uterine scars. The aim of this study was to determine the influence of several previous Caesarean sections on the LUS state in term pregnant women. The prospective study included 62 pregnant women with one or more previous Caesarean sections – the examined group, and 50 pregnant women without Caesarean section – the control group, that after the 37th week of pregnancy had undergone the transvaginal ultrasonic measuring of the thickness of the LUS muscular tissue. In 57 pregnant women from the examined group delivered with another Caesarean section, we estimated, intraoperatively, the LUS integrity in the scar area. On the same occasion, in the scar area, the presence of defect – partial or complete was detected. The research pointed out that the average LUS thickness in the examined group – 1.92±0.95 mm was statistically significantly lower compared to the control group – 2.68±0.97 mm (p<0.001). The average LUS thickness in 52 examined women with one Caesarean section was 1.92±0.97 mm, and in 9 women with two Caesarean sections the average thickness was lower – 1.78±0.82 mm, which does not represent a statistically significant difference (p=0.85). In one pregnant woman with three Caesarean sections, the LUS thickness was 3.30 mm. We registered the total of 13 pregnant women with a defect in the Caesarean section scar area (12 partial and 1 complete defects), in 12 women after one Caesarean section and in 1 woman after two Caesarean sections. The research results show that women with previous Caesarean section have significantly thinner LUS, compared to the group of pregnant women without scars. With the increasing number of previous Caesarean sections, the LUS thickness decreases, but the difference is not statistically significant. Intraoperatively, the presence of certain LUS classes compared to the number of previous Caesarean sections is not significantly different. Furthermore, the increase in the number of Caesarean sections does not involve a statistically significant increase in the frequency of Caesarean section scar defects, which is in accordance with other authors’ results. Acta Medica Medianae 2010;49(2):29-33.
Key words: uterine segment – LUS, Caesarean section, scar, transvaginal ultrasound