Uterine rupture in women attempting a vaginal birth following prior cesarean birth

To determine (1) if there are any common features to fetal heart rates (FHR) and uterine activity patterns before uterine rupture, (2) if neonatal outcomes as reflected by cord blood gases are associated with the length of fetal bradycardia, and (3) if there is an increase in maternal and/or neonatal length of stay in women who experience uterine rupture during labor as compared with women following repeat cesarean section.

Maternal and fetal records of 11 women identified by the ICD-9 code as having had a uterine rupture between 1990 and 1995 were retrospectively reviewed.

No one common feature in FHR patterns or uterine activity existed before uterine rupture other than bradycardia, although variable and/or late decelerations commonly preceded the bradycardia. Of the neonates, 91% had cord blood pH of <7.0 and 45% had base excess greater than 15 meq/l. Of those fetuses experiencing bradycardia, 55% had placental abruption. Maternal length of stay 5 days or greater occurred in 36% of those with uterine rupture. Seventy-three percent of the neonates required admission to the Neonatal Intensive Care Unit (NICU). Despite acidemia as shown by cord pH, none of the neonates experienced seizures or multiorgan dysfunction.

There is no one specific FHR or uterine activity pattern that indicates the onset of a uterine rupture, although variable and/or late decelerations occur before the onset of an FHR bradycardia. In the present study, neonatal admissions to the NICU were increased and pH values were below 7.0 in 91% when uterine rupture occurred. A decrease or cessation of uterine tone was not observed. Maternal length of stay was slightly increased following uterine rupture.