Spontaneous (non-traumatic) intraperitoneal rupture of the bladder in a 37-year-old pregnant woman was repaired at laparotomy. Nine months later she again presented with an intraperitoneal bladder rupture during pregnancy and fatal sepsis. Histological examination of the resected bladder wall showed acute ulcerative and necrotising cystitis. All patients with apparently spontaneous bladder rupture should undergo full urological evaluation to identify possible disease which might lead to recurrent rupture.