Obstetric Uterine Rupture of the Unscarred Uterus: A Twenty-Year Clinical Analysis

<i>Background:</i>Rupture of the unscarred uterus is a rare and potentially catastrophic event. We retrospectively reviewed the records of patients with this condition to analyze their obstetric and gynecologic history and evaluate maternal and perinatal morbidity and mortality. <i>Methods:</i>A total of 11 cases of rupture of the unscarred gravid uterus were managed at Mackay Memorial Hospital from January 1984 to September 2003. Data extracted from the records included the use of uterine stimulants, instrumental delivery, and prior abortion by instrumentation, clinical features, treatment, and maternal and fetal morbidity and mortality. <i>Results:</i>The incidence of unscarred uterine rupture is 0.009% during the 20-year study period. The most common contributing factors were prior abortion by instrumentation and the use of uterotonic agents, in three cases respectively. Fetal distress occurred in six cases and postpartum hemorrhage in two. There was no maternal death, but in two cases, there was intrauterine fetal demise or perinatal death. <i>Conclusion:</i>Though unexpected in a woman with an unscarred uterus, rupture should be considered as a possible cause of fetal distress or unusual pain or hypotension in the mother.