336 The assessment of the “july effect” on induction of labor

Abstract

There is a perceived increase in clinical risk during the year when graduating medical students begin residencies. We sought to investigate for the July Effect on primary cesarean delivery (CD) and maternal complications in Obstetrics. This is a retrospective, population-based cohort study of nulliparous, term, and singleton patients undergoing induction of labor [IOL] via prostaglandin ripening at single institution from July 2014-June 2017. Excluded were: multiparas, active labor, or non-prostaglandin-based induction methods. Patient charts were interrogated and data stratified by time of IOL. July Effect was analyzed as July 1-September 30, against remaining months of the year. Primary outcome was CD rate. Secondary outcomes included obstetric anal sphincter injury, shoulder dystocia, wound complications, postpartum hemorrhage, transfusion need, puerperal fever, and maternal ICU admission. Data was analyzed using chi squared, logistic regression, odds ratio and 95% confidence interval with <0.01 used as significant. 16,721 deliveries occurred between July 1, 2014 and June 30, 2017. 2217 patients were included for analysis. 1144 patients were induced with dinoprostone and 1073 patients were induced with misoprostol. There was no significant difference in likelihood of CD between July – September when compared to the remaining year (OR 0.9 (0.8-1.1), p 0.442). Misoprostol was associated with lower likelihood of CD (OR 0.6 (0.5-0.7), p<0.001), while age >35 was associated with greater likelihood of CD (OR 1.8 (1.5-2.2), p<0.001). There was no increase in maternal complications during potential July Effect. There was no significant difference in the likelihood of CD between groups. We did not identify July Effect for CD nor maternal complications in this obstetrical cohort. Though further research is needed across institutions, July Effect is likely not a relevant concern in Obstetrics.