PP24 Decomposing public/private differences in elective and emergency caesarean delivery rates among nulliparous women

Abstract

Background Current evidence points to a difference in the rate of caesarean section depending on whether the delivery is funded privately or publicly in Ireland. This paper evaluates the extent of the difference in elective and emergency caesarean delivery rates between public and private women in public maternity hospitals, in addition to quantifying the contribution of different maternal and clinical characteristics in explaining the difference in the rates. Methods Cross-sectional analysis using a combination of two routinely collected administrative databases was performed. Data were for 19 public hospital maternity units in the Republic of Ireland. A non-linear extension of the Oaxaca-Blinder method was used to decompose the difference between public and private elective/emergency caesarean delivery rates into the proportion explained by the differences in observable maternal and clinical characteristics and the proportion that remains unexplained. Nulliparous women with a singleton delivery (live or stillborn) in hospital who were discharged between January 1st and December 31st 2009 were included. We stratified across elective CS (ELCS) and emergency CS (EMCS). Results Of 29,870 births, 7,792 were delivered via CS (26.1%), 79.6% of which were coded as EMCS deliveries. Higher prevalence of ELCS was associated with having had a CS previously (69.2%), breech presentation (64.5%), and other malpresentation (53.5%). Higher prevalence of EMCS was associated with placenta praevia or placental abruption (55.3%), prematurity (44.6%), dystocia in labour (40.6%), and fetal distress (31.0%). Slightly more than half of the variation in ELCS rates between public and private patients was explained by our models (55.9%). All of the variation for EMCS could be explained. Conclusion Controlling for clinical and maternal risk factors explained approximately half of the variation in ELCS rates across publicly and privately funded deliveries. This raises a question of what other factors may be explanatory. Given the globally increasing CS rates and both the benefits and harms this is associated with, further research is required to identify such factors.