Unintended lower‐segment hysterotomy extension at cesarean delivery and the risk for uterine rupture during a subsequent trial of labor

Abstract

ObjectiveTo evaluate the association between unintended uterine extension in cesarean delivery and uterine scar disruption (rupture or dehiscence) at the subsequent trial of labor after cesarean delivery (TOLAC).MethodsThis is a multicenter retrospective cohort study (2005–2021). Parturients with a singleton pregnancy who had unintended lower‐segment uterine extension during the primary cesarean delivery (excluding T and J vertical extensions) were compared with patients who did not have an unintended uterine extension. We assessed the subsequent uterine scar disruption rate following the subsequent TOLAC and the rate of adverse maternal outcome.ResultsDuring the study period, 7199 patients underwent a trial of labor and were eligible for the study, of whom 1245 (17.3%) had a previous unintended uterine extension and 5954 (82.7%) did not. In univariate analysis, previous unintended uterine extension during the primary cesarean delivery was not significantly associated with uterine scar rupture in the following subsequent TOLAC. Nevertheless, it was associated with uterine scar dehiscence, higher rates of TOLAC failure, and a composite adverse maternal outcome. In multivariate analyses, only the association between previous unintended uterine extension and higher rates of TOLAC failure was confirmed.ConclusionA history of unintended lower‐segment uterine extension is not associated with an increased risk for uterine scar disruption following subsequent TOLAC.

Impact of prior use of topical hemostatic agents on trial of labor after cesarean: Insights from a multicenter cohort study

“…The details of the study have previously been reported. 21 For this analysis, patients with singleton pregnancies and one prior low-segment cesarean delivery who attempted a first trial of labor between 24 and 42 weeks of pregnancy were included. Several exclusion criteria were applied: patients who did not have both the primary cesarean and subsequent TOLAC at the study hospitals,; patients with elective repeat cesarean delivery or prelabor indications for cesarean; and those with previous multiple cesareans, multifetal gestation, fetal major malformation, out-of-hospital deliveries, and a malformed uterus.…”