Perinatal outcome in births after a previous cesarean section at high trial of labor rates.

Trial of labor (TOLAC) is an option in most pregnancies after a cesarean section. The objective of the study was to compare perinatal outcome in TOLAC and non TOLAC deliveries, in a population with high TOLAC rates MATERIAL AND METHODS: Cohort study, based on population data from the Medical Birth Registry of Norway. We included term, cephalic, single, second deliveries, 1989-2009, after a first cesarean section (n=43 422). TOLAC, TOLAC failure, and non TOLAC deliveries, after high and low risk pregnancies (no risk / any risk), were compared with regard to offspring mortality, five minute Apgar score < 7, five minute Apgar score < 4, transfer to a neonatal intensive care unit, and neonatal respiratory distress syndrome (NRDS) RESULTS: Statistically significant differences were observed (p < 0.05): In the low risk group, the offspring mortality was 2.3/1000 in TOLAC compared to 0.9/1000 in non TOLAC. In the high risk group, the offspring mortality was 3.7/1000 in TOLAC compared to 0.9/1000 in non TOLAC, and the rate of five minute Apgar score < 4 was 3.1/1000 in TOLAC compared to 0.9/1000 in non TOLAC. In both risk groups, TOLAC deliveries had a higher rate of five minute Apgar score < 7. In the low risk group, non TOLAC had a higher rate of NRDS CONCLUSIONS: We observed excess risk of offspring mortality and low five minute Apgar score in TOLAC. Possible causes and preventive measures should be explored. This article is protected by copyright. All rights reserved.