Comparison of Fetomaternal Outcomes between Scarred and Unscarred Uterus in Placenta Previa Cases

Abstract

Background: Placenta previa remains a significant obstetric challenge, especially when compounded by a history of uterine scarring such as prior cesarean sections. A scarred uterus is increasingly recognized for its association with abnormal placentation, increased surgical complexity, and adverse fetal outcomes. With rising cesarean rates globally, understanding the comparative risks posed by scarred versus unscarred uteri in placenta previa is essential for optimizing clinical management and maternal-neonatal safety. Objective: To compare fetomaternal outcomes between scarred and unscarred uteri among women diagnosed with placenta previa. Methodology: This descriptive case series was conducted in the Department of Obstetrics and Gynaecology, Shalamar Hospital, Lahore, Pakistan, from November 2024 to April 2025. A total of 176 pregnant women (88 with scarred uteri and 88 with unscarred uteri) diagnosed with placenta previa beyond 28 weeks gestation was included using non-probability purposive sampling. Data were collected through structured proformas and analyzed using SPSS version 22. Results: Women with scarred uteri had significantly higher rates of postpartum hemorrhage (68.2% vs. 40.9%; p<0.001), morbidly adherent placenta (22.7% vs. 1.1%; p<0.001), and cesarean hysterectomy (59.1% vs. 4.5%; p<0.001) compared to those with unscarred uteri. They also exhibited increased total blood loss ≥1000ml (62.5% vs. 29.5%; p<0.001) and maternal shock (23.9% vs. 5.7%; p=0.001). Neonates born to mothers with scarred uteri experienced significantly more complications, including low birth weight (50.0% vs. 29.5%; p=0.006), respiratory distress syndrome (20.5% vs. 5.7%; p=0.005), premature birth <37 weeks (59.1% vs. 43.2%; p=0.039), and poor APGAR scores at 5 minutes (<7 in 27.3% vs. 6.8%; p=0.001). Conclusion: Placenta previa in women with a scarred uterus is associated with markedly increased risks of severe maternal and neonatal complications. These findings underscore the clinical importance of thorough obstetric history-taking, early identification of placenta previa, and vigilant intrapartum management in women with previous cesarean deliveries. Rationalizing cesarean use and improving antenatal surveillance may mitigate the burden of placenta previa-related morbidity in subsequent pregnancies.