Ten years of uterine rupture in an Australian tertiary hospital

Abstract

Complete uterine rupture is a rare and serious complication of pregnancy. Although most commonly associated with attempted vaginal birth after caesarean (VBAC), rupture also occurs in atypical/non-VBAC cases. This retrospective, single-tertiary-institution observational study aimed to assess the prevalence and morbidity of complete uterine rupture during 2010-2020. Hospital discharge codes and local maternity databases identified uterine rupture cases, with medical record reviews confirming the diagnosis, distinguishing complete rupture from dehiscence, and extracting additional data. VBAC attempt was defined as planned labour trial after one prior caesarean. Over the decade, 27 complete ruptures occurred among 58614 women, a rate of 4.6 per 10000 births. One woman with three successive fundal ruptures had only the first included in further analysis, leaving 25 discrete women; 19 ruptures occurred in term planned VBAC attempts and six in preterm atypical/non-VBAC cases (two nulliparas and four women with multiple prior caesareans). The VBAC-attempt rupture rate was 0.74%, similar to published reports. All five perinatal deaths occurred in preterm atypical/non-VBAC cases. In the term VBAC-attempt group, rupture-related perinatal morbidity included four cases (21%) of hypoxic-ischaemic encephalopathy, with two cases (11%) of cerebral palsy at follow-up. Overall, perinatal morbidity was highest with total fetal extrusion. Maternal blood loss ≥1500mL or transfusion was almost threefold higher, and postnatal length-of-stay was three days longer, after vaginal than caesarean birth, with delay in rupture recognition being a factor. A high suspicion index for uterine rupture is imperative during any labour, particularly in the scarred uterus, with vigilance continuing after successful vaginal birth.