ULTRASONOGRAPHIC MEASUREMENT OF UTERINE LOWER SEGMENT SCAR THICKNESS IN CASES OF PREVIOUS ONE CAESAREAN SECTION AND OBSTETRIC OUTCOME

Abstract

ABSTRACT

Background:  The danger of uterine rupture in future pregnancies is one of the concerns about the long-term effects of uterine scars from prior cesarean births. The thickness of the scar in the lower uterine segment may be measured ultrasonographically to offer important information about the scar's integrity and to assist forecast the likelihood of problems in subsequent pregnancies.

Objective: To determine the association of uterine lower segment scar thickness in cases of previous one caesarean section with obstetric outcome   

Methods: This was a cohort study conducted at Department of Radiology, KRL hospital, Islambad, during time period six months from February to July, 2024. Total 123 women were included in the study who had undergone previous one cesarean section (elective/emergency) during their previous pregnancy and willing to go for vaginal birth after cesarean section. All women underwent detailed clinical examination and transabdominal ultrasound evaluation for scar thickness. The adopted cut of value for scar thickness was set at 3. In cases where the scar thickness exceeded 3 mm, a trial of labor was decided upon with the patient's permission; in cases where the scar thickness was less than 3 mm, an elective repeat lower segment cesarean section (LSCS) was decided upon. Outcome variables include type of delivery and neonatal weight.

Results: Among women 61.80% had Vaginal birth after caesarean section and 38.20% had repeat cesarean section. Significant difference was seen in uterine lower segment scar thickness between women who had VBAC and LSCS. Highest frequency of VBAC was seen among women with scar thickness between 3.1-4.0. Weight of neonate had significant association with delivery type. It was observed that neonates with weight >3.5 kg had higher frequency of LSCS. i.e. (p-value<0.001). The area under the curve value for ROC curve was 0.617.  The ROC curve suggest that using a cut of value for uterine lower segment scar thickness as 3.15 mm among women with previous one cesarean section could predict VBAC with sensitivity 80.3% and specificity as 61.7%

Conclusion: In the current study, highest rate of successful vaginal birth after caesarean was found in women with scar thickness between 3.1 mm and 4.0 mm.  

Key Words: Scar, Thickness, Previous, Caesarean section, lower uterine segment, Ultrasonography