This retrospective cohort study examined 143/39,895 (0.36%) consecutive born-before-arrival (BBA) births. The incidence of BBA births doubled from 0.26% in 2005 to 0.5% in 2009. This increase was mainly attributed to the increase of non-Irish nationals and patients from low socioeconomic groups attending for antenatal care. Poor social background was often coupled with current or past substance misuse and/or a diagnosis of an infectious disease. While there was no excess in maternal morbidity, the perinatal mortality rate among BBA births was three-fold increased (27.9/1,000) when compared with the overall rate for all inborn babies in our hospital (8.5/1,000) but significantly less than previously published (58.4/1,000). Results of our study call for continuing training of paramedic staff involved in these deliveries and neonatal resuscitation. Given the easy accessibility of antenatal services in Ireland, this study highlights the urgent need for optimising parental education and care in this vulnerable group of patients.