Risk of Uterine Rupture in Australian Women Attempting Vaginal Birth After 1 Prior Cesarean Section

Abstract

2 received platelets, 2 received coagulation factor, and all received fresh-frozen plasma and/or cryoprecipitate. Of the 19 women with AFE who delivered in a hospital, 5 stillbirths and 1 neonatal death were reported. Three perinatal deaths occurred among surviving mothers, and the perinatal mortality rate for mothers who died was 50%. Follow-up data for the 13 survivors indicated that 6 of these patients required hospitalization within 12 months of the AFE episode for a variety of reasons, some of which could have been unrelated to the AFE. Two survivors had subsequent births during the study period. Of note, both women experienced AFE and an associated perinatal death during the second birth.Although 66% of women and infants survived AFE, many had severe morbidity. Based on their data analysis, the investigators were able to identify 2 new risk factors for AFE-induction with vaginal prostaglandin and manual removal of the placenta. Compared to data from the United Kingdom, the incidence rate reported in this Australian study was higher but the maternal and perinatal case fatality rates were similar. In contrast, the incidence rates reported in database studies from the United States and Canada were higher and the maternal mortality rates were lower compared to the Australian data.O ver the last 3 decades, cesarean delivery rates have increased worldwide. A concern exists for uterine rupture in these women during subsequent pregnancies. Previous studies have found that the risk of uterine rupture among women who attempt vaginal birth after cesarean (VBAC) is higher compared to women who do not labor but rather undergo elective repeat cesarean delivery. The risk of rupture has been reported to be highest when labor is induced with prostaglandins. This population-based retrospective cohort study was designed to quantify the risk of uterine rupture during the second singleton birth when the first birth had been by cesarean delivery.The data were obtained from databases from the 4 largest Australian states that include 60% of the annual births in the country. All women having a singleton second pregnancy during 1998 to 2000 were included if the first birth was a live-born singleton infant delivered by cesarean section (CS). Women were placed in the following subgroups: (1) repeat CS without labor (elective cesarean), (2) spontaneous onset of labor with oxytocin augmentation, (3) induction of labor with oxytocin, (4) induction of labor with prostaglandins, (5) induction of labor with both oxytocin and prostaglandins, and (6) induction of labor with neither oxytocin nor prostaglandins. Each subgroup was compared with a reference group that included women with spontaneous onset of labor without oxytocin augmentation. Cases of uterine rupture were identified from the International Classification of Diseases (ICD) codes. The uterine rupture was then confirmed by review of case records.During the study period, data from 29,008 women were found that met the inclusion criteria. The mean age was 31.2 years, and 22% were Z35 ...