Unplanned out-of-hospital birth and risk factors of adverse perinatal outcome: findings from a prospective cohort

Abstract

Background: In France, while most babies are delivered at hospital, emergency medical services (EMS) weekly manage calls for unplanned out-of-hospital births. The objective of our study was to describe neonatal morbidity and mortality, defined as death or neonatal intensive care unit hospitalization at Day 7, in a prospective multicentric cohort of unplanned out-of-hospital births.

Methods: We prospectively analyzed out-of-hospital births from 25 prehospital EMS units in France. The primary outcome was neonatal morbidity and mortality, and the secondary outcome was risk factors associated with neonatal morbidity and mortality. A univariate logistic regression was first made, followed by a multivariate logistic regression with backward selection.

Results: From October 2011 to August 2018, a total of 1670 unplanned out-of-hospital births were included. Of these, 1652 (99.2%) were singleton and 1537 (93.5%) had prenatal care. Maternal mean age of the study population was 30 ± 5.5 (range 15 to 48). The majority of women were multiparous, but 13% were nulliparous. Overall, 45.3% of these unplanned out-of-hospital births were medically-driven, either by phone during medical regulation (12.5%) or on scene by the prehospital emergency medical service units (32.9%). The prevalence of neonatal morbidity and mortality was 6.3% (n = 106) after an unplanned out-of-hospital birth (death before Day 7: n = 20; 1.2%). The multivariate logistic regression found that multiparity (adjusted Odds Ratio = 70.7 [4.7-1062]), prematurity (adjusted Odds Ratio = 6.7 [2.1-21.4]), maternal pathology (adjusted Odds Ratio = 2.8 [1.0-7.5]) and hypothermia (adjusted Odds Ratio = 2.8 [1.1-7.6]) were independent predictive factors of neonatal morbidity and mortality.

Conclusions: Our study assessed for the first time risk factors for adverse perinatal outcome in a large and multicenter cohort of unplanned out-of-hospital births. We have to improve temperature management in the out-of-hospital field and future trials are required to investigate strategies to optimize newborns management in the prehospital area.

Keywords: Birth before arrival; Emergency medical services; Out of hospital birth; Out-of-hospital delivery; Prehospital delivery; Unplanned delivery.