Uterine rupture and factors associated with adverse outcomes.

Purpose: To review cases of uterine rupture and identify risk factors associated with adverse outcomes.

Methods: This study is a retrospective cohort of complete uterine ruptures diagnosed in a large hospital system in Massachusetts between 2004 and 2018. Baseline demographics, labor characteristics and outcomes of uterine rupture were collected from medical records.

Results: A total of 173 cases of uterine rupture were identified. There were 30 (17.3%) women with an unscarred uterus, while 142 (82.1%) had a scarred uterus. Adverse outcomes (n = 89, 51.4% of cases) included 26 (15.0%) hysterectomies, 55 (31.8%) blood transfusions, 18 (10.4%) bladder/ureteral injuries, 5 (2.9%) reoperations, 25 (14.5%) Apgar scores lower than 5 at 5 min and 9 (5.2%) perinatal deaths. Uterine rupture of a scarred uterus was associated with decreased risk of hemorrhage (OR 0.40, 95% CI 0.17-0.93), blood transfusion (OR 0.27, 95% CI 0.11-0.69), hysterectomy (OR 0.23, 95% CI 0.08-0.69) and any adverse outcome (OR 0.34, 95% CI 0.13-0.91) compared with unscarred rupture. Uterine rupture during vaginal delivery was associated with increased risk of transfusion (OR 6.55, 95% CI 1.53-28.05) and hysterectomy (OR 8.95, 95% CI 2.12-37.72) compared with emergent C-section.

Conclusions: Although rare, uterine rupture is associated with adverse outcomes in over half of cases. Unscarred rupture and vaginal delivery demonstrate increased risk of adverse outcomes, highlighting the need for early diagnosis and operative intervention.