OBJECTIVE: To estimate the time from the diagnosis of uterine rupture to delivery that would prevent adverse neonatal sequelae.
METHODS: Cases of uterine rupture from January 1, 2000, to December 31, 2009, were identified in nine hospitals in the Intermountain Health Care system and at the University of Utah. Maternal demographics, labor characteristics, and neonatal outcomes were obtained. Primary adverse outcome was abnormal umbilical artery pH level less than 7.0 or 5-minute Apgar score less than 7. Adverse secondary outcome included fetal or neonatal death and neonatal neurologic injury attributed to uterine rupture.
RESULTS: Thirty-six cases of uterine rupture occurred during 11,195 trials of labor after cesarean delivery. Signs of uterine rupture were fetal (n=24), maternal (n=8), or a combination of maternal and fetal (n=3). In one case, uterine rupture was not suspected. Mean time to delivery from the onset of symptoms or signs for the primary adverse outcome group (n=13) was 23.3 (±10.8) minutes compared with 16.0 (±7.7) minutes for those without an adverse outcome (P=.02). No neonate delivered in fewer than 18 minutes had an umbilical pH level below 7.0. Three neonates delivered at more than 30 minutes met criteria for an adverse secondary outcome.
CONCLUSION: The frequency of uterine rupture was 0.32% in patients attempting a trial of labor after cesarean delivery. Neonates delivered within 18 minutes after a suspected uterine rupture had normal umbilical pH levels or 5-minute Apgar scores greater than 7. Poor long-term outcome occurred in three neonates with a decision-to-delivery time longer than 30 minutes.
LEVEL OF EVIDENCE: II