Ultrasonographic Evaluation of Uterine LSCS Scar and its Impact on Maternal Outcomes: A Cross-sectional Study

Introduction: The evaluation of uterine scars following Caesarean Section (CS) is essential for predicting delivery outcomes, particularly in patients considering Vaginal Birth After Caesarean (VBAC) or those undergoing repeat Lower Segment Caesarean Section (LSCS). Ultrasonography has emerged as a valuable tool for assessing caesarean scars, providing insights into critical scar features such as thickness, shape, continuity, and echogenicity. These factors play a significant role in determining the risk of complications, including uterine rupture and scar dehiscence, and influencing the decision-making process for VBAC or repeat LSCS. Aim: The study focused on identifying critical scar features, including thickness, continuity, and echogenicity, and their impact on delivery outcomes, specifically VBAC success rates and complications during repeat LSCS. Materials and Methods: This hospital-based, cross-sectional study was conducted from February 2022 to January 2025 at a tertiary care hospital. A sample of 284 pregnant women, at a gestational age of over 35 weeks with a history of previous CS, was recruited. Participants underwent clinical evaluation, including a detailed history, physical examination, and ultrasonographic assessment of the LSCS scar. Scar parameters were measured transabdominally, including thickness, shape (triangular/ballooning), continuity, and echogenicity using transvaginal ultrasound imaging. Categorical variables were summarised as percentages, while continuous variables were expressed as mean±standard deviation. Results: The majority of patients (201, 70.77%) were in the 26- 30 age group, with 249 (87.68%) patients falling between 150- 160 cm in height and 139 (48.94%) patients weighing 56-60 kg. A high proportion (236, 83.1%) resided in rural areas, and 227 (79.93%) patients belonged to the lower socioeconomic class. Scar patterns indicated that 55 (98.21%) cases of vaginal deliveries had a triangular scar, with only 1 (1.79%) had ballooning pattern, while 180 (78.95%) cases of LSCS had a triangular scar and 48 (21.05%) cases exhibiting a ballooning pattern. Thinner scars (<3 mm) were associated with a higher incidence of repeat LSCS (195, 85.09%). Continuous scars were linked to successful VBAC outcomes in 52 (92.86%) cases. Hyperechoic scars were found in 56 (100%) of vaginal deliveries, whereas hypoechoic (46, 20.18%) and isoechoic scars (12, 5.25%) were more common in LSCS cases. Conclusion: Ultrasonographic evaluation of the LSCS scar plays a critical role in predicting delivery outcomes. Triangular scars and thicker scar measurements (>3 mm) were associated with higher success rates for VBAC, while ballooning patterns and thinner scars (<3 mm) were linked to higher rates of repeat CS.