Outcome of subsequent pregnancies in women with complete uterine rupture: A population-based case-control study.

INTRODUCTION: In the attempt of a trial of labor after a cesarean section approximately one in 200 women experience a complete uterine rupture. As a complete uterine rupture is associated with an adverse perinatal outcome, data regarding subsequent pregnancies are needed to provide proper care and guidance to women with a complete uterine rupture when informing them of future possibilities. The objective of this study was to investigate the fetal and maternal outcomes in subsequent pregnancies after a complete uterine rupture.

MATERIAL AND METHODS: Retrospective population-based case-control study. Denmark 1997-2017. A total of 175 women with complete uterine rupture during an attempted trial of labor after cesarean (TOLAC) at term (cases) and a corresponding group of 272 women with no uterine rupture during an attempted TOLAC at term (controls) were labeled as index deliveries. Index deliveries were included from January 1, 1997 to December 31, 2008. From the date of the index delivery to December 31, 2017 the information on subsequent pregnancies and deliveries, and on referral to hospital with any obstetric or gynecological diagnosis were retrieved from the Danish Medical Birth Registry and National Patient Registry. Main outcome measures were miscarriage, perinatal death, neonatal morbidity, preterm birth, and recurrence of uterine rupture. Outcome measures were compared between cases and controls.

RESULTS: After the index deliveries; there were 109 pregnancies and 70 deliveries after gestational age 22+0  weeks in the population of cases. In the population of controls, there were 183 pregnancies and 126 deliveries after 22+0  weeks. Cases had a significantly higher risk of miscarriage (odds ratio [OR] 3.99; 95% confidence interval [CI] 1.36-13.17). The incidence of uterine rupture was 8.6% among cases and 0.8% among controls (OR 11.7; 95% CI 1.36-543.1). Among cases, 98.6% had live-born infants, and none of these had severe neonatal morbidity. No significant association was found between previous complete uterine rupture and preterm delivery, placenta previa, hysterectomy in relation to subsequent births, diagnosis such as meno/metrorrhagia, dysmenorrhea, or procedures such as hysteroscopy or hysterectomy.

CONCLUSIONS: In pregnancies following complete uterine rupture continuing after 22+0  weeks, maternal and fetal outcomes are good when managed promptly with cesarean delivery.