When to expect the unexpected: uterine rupture before onset of labour

Uterine rupture is a feared complication when a woman with a uterus scarred by a caesarean section (CS) is in labour. The increased awareness of the possibility of uterine rupture and dramatic consequences including perinatal asphyxia has lead to guidelines for management when undertaking a trial of labour after caesarean section Uterine rupture occurs in an estimated 35 per 10 000 women with a previous CS undergoing labour (INOSS study of uterine rupture, BJOG 2019;126:370-381), but is extremely rare before the onset of labour and in the unscarred uterus. Our knowledge of prelabour uterine rupture is confined merely to a small number of published case reports and case series in the literature.