555: Failed induction is not to blame for rising cesarean section rates

Abstract

We sought to examine rates of induction and cesarean section (CS) in a large cohort of deliveries across three tertiary referral centers over 8 years to explore how induction influences primary CS rates. Indications for primary CS were examined in detail for one of the centers. This is a retrospective analysis of prospectively gathered data carried out at three large maternity hospitals in Dublin from 2006-2014. All cases of inductions and CS for viable births were recorded during this study period and analyzed for trends. From 2006-2014 there were 232,875 viable births across all three sites. For the study population as a whole, the overall rates of induction and CS increased from 22% to 29% (p=0.0001), and 23% to 28% (p=0.0001) respectively. Regarding one center, a significant increase in primary CS (n=13,392, p=0.0001) was identified (Figure 1), the most common indication being an increasing rate of non-reassuring fetal heart monitoring (NRFHM) (25.8% to 32.4% (p=0.0001)(Figure 2)). At this center, the rate of primary CS due to failed induction remained unchanged (4.8->4.5%, p=0.08791) (Figure 3.) Although induction, total and primary CS rates increased over the course of the study period, the rate of primary CS due to failed induction remained surprisingly unchanged. Our data suggest that NRFM is the most common indication for rising primary CS, suggesting increasing numbers of pregnancies at risk of fetal hypoxia in labor. In conclusion, this data challenges the notion that the increasing primary CS rate is associated with a rising trend in induction of labor.