Silent Danger: Risk Factors and Outcomes of Fortuitously Discovered Uterine Rupture - A 41-Case Cohort Study.

Abstract

Background: Uterine rupture (UR) remains a major cause of maternal morbidity, especially in low-resource settings. While typically detected during labor, some cases are clinically silent, discovered incidentally during imaging/surgery, highlighting a knowledge gap in risk assessment. In Tunisia, 1.5% of pregnancies involve UR, mostly scar-related. The study aim was to identify factors associated with the development of fortuitously discovered UR in cases that were incidentally found during pregnancy or delivery.

Methods: This was retrospective, longitudinal cohort study conducted over an eleven-year period, from January 2014 to December 2024, at the Gynaecology and Obstetrics department B, Charles Nicolle Hospital, Tunis, Tunisia. Asymptomatic UR cases (complete/incomplete) were analysed to compare clinical profiles, identify risk factors, and assess maternal and neonatal outcomes.

Results: A total of 41 cases of asymptomatic UR were included, which accounted for an average of 50% of the UR cases. In a cohort comparing complete UR cases (N=27) and incomplete UR cases (N=14), significant differences in duration of pregnancy and labor were found. The mean gestational age was longer in the incomplete UR group (p=0.03), and the duration of labor was also significantly longer (p=0.006). No significant differences were observed in sociodemographic characteristics, quality of prenatal care, or complications such as gestational diabetes or preeclampsia. Nonsignificant factors included pregnancy interval, scars number and labor stagnation. The analysis showed two significant predictors of complete UR outcomes. Prolonged labor (>220 minutes) was strongly associated with increased odds of complete UR (OR=45.231, 95% CI=2.591-789.486, p=0.009) and lower maternal weight (<68 kg) correlated with reduced odds of incomplete UR (OR=0.033, 95% CI=0.001-0.837, p=0.039), suggesting a protective effect per kilogram maternal body weight decrease.

Conclusion: Findings redefine UR as part of a broader clinical spectrum, not just an acute obstetric complication. Early identification of associated risk factors such as prolonged labor and maternal weight could inform targeted surveillance in high-risk pregnancies.