Abstract

BACKGROUND AND OBJECTIVES: The rate of Caesarean delivery has been increasing steadily over the past two decades and is the most common obstetric operative procedure worldwide. Previous caesarean section has been found to be the most common indication due to the inability to precisely confirm the integrity of the scarred lower uterine segment (LUS). The purpose of this study is to evaluate the accuracy of ultrasonography (USG) in determining the LUS thickness in previous caesarean section patient.
MATERIALS AND METHOD: The present observation study was conducted on 120 pregnant women who had previous caesarean section and were planned for an elective CS in the department of obstetrics and gynecology, ESIC MC & PGIMSR, Rajajinagar, and Bangalore from January 2019 to June 2020. LUS thickness was measured by Transabdominal scan (TAS) and then correlated to scar integrity assessed intraoperatively. The sensitivity, specificity, positive and negative predicted values of the sonographic LUS thickness was determined.
RESULTS: Ultra sonographic LUS thickness assessed correlated significantly with intraoperative LUS thickness. (r value 0.272, p<0.001) The mean thickness of LUS in women with normal scar was 4.2 + 0.7 mm and in women with abnormal LUS was 2.8 + 0.5 mm the difference being highly significant (p < 0.001). A cut off of 3.5 mm was derived from ROC with sensitivity, specificity, PPV NPV of 90.3%, 82%, 64.2% , 92.6% respectively. In our study the rate of scar dehiscence/rupture noted was 5% and only 1 woman had rupture of uterus.
CONCLUSION: LUS measurement is a useful clinical tool in the prediction of scar integrity. It should be performed routinely in all women who have had a previous caesarean section so that a large proportion of women could be considered for a trial of labour which would decrease the cost of health care and maternal morbidity rate.