Planned Out-of-Hospital Birth and Birth Outcomes

The rates of planned out-of-hospital birth (births intended to occur at home or at a freestanding birth center) have increased in the United States in recent years. The rate of birth at home increased by 20% between 2004 and 2008 and by approximately 60% between 2008 and 2012, reaching 0.89% of all births, whereas the rate of use of birth centers increased from 0.23% in 2004 to 0.39% in 2012. Oregon had the highest home birth rate in the United States in 2012 (2.4%); it also had a 1.6% rate of deliveries at birth centers. The significance of studies assessing the perinatal risks of planned out-of-hospital birth against hospital birth has been limited by cases in which transfer to a hospital is required and a birth that was initially planned as an outof- hospital birth is misclassified as a hospital birth. Oregon introduced new questions on the birth certificate in January 1, 2012, to document the planned place of delivery at the time a woman began labor. This population-based, retrospective cohort study analyzes records of all births that occurred in Oregon during 2012 and 2013 using data from the revised Oregon birth certificates. These certificates allowed for the disaggregation of hospital births into the categories of planned in-hospital births and planned out-of-hospital births that took place in the hospital after a woman's intrapartum transfer to the hospital. The analyzed aspects included perinatal morbidity and mortality, maternal morbidity, and obstetrical procedures according to the planned birth setting (out of hospital vs hospital). The study sample included 79,727 cephalic, singleton, term, nonanomalous deliveries in Oregon in 2012 and 2013. Results showed that planned out-of-hospital birth was associated with a higher rate of perinatal death than was planned in-hospital birth (3.9 vs 1.8 deaths per 1000 deliveries, P = 0.003; odds ratio after adjustment for maternal characteristics and medical conditions, 2.43; 95% confidence interval [ CI], 1.37-4.30; adjusted risk difference, 1.52 deaths per 1000 births; 95% CI, 0.51-2.54). In addition, the odds for neonatal seizure were higher, and the odds for admission to a neonatal intensive care unit were lower with planned out-of-hospital births than with planned in-hospital birth. It was also noted that planned out-of-hospital birth were strongly associated with unassisted vaginal delivery (93.8% vs 71.9% with planned in-hospital births; P < 0.001) and also with decreased odds for obstetrical procedures. In conclusion, the study shows that the rates of obstetrical interventions were lower, but the risks of perinatal death and other adverse neonatal outcomes were higher with planned out-of-hospital birth than with planned in-hospital birth. Although the absolute differences in the risks of adverse neonatal outcomes in both the settings were small, the findings highlight the effect that the misclassification of intended birth setting has on the accuracy of US vital statistics.