Impact and factors affecting unplanned out-of-hospital birth on newborns at University Hospital compared to in-hospital born newborns

Background: This retrospective study examined maternal risk factors and newborn outcomes for unplanned out-of-hospital births (UOHB) brought to an inner-city hospital (Newark, NJ, USA). Unplanned out-of-hospital births have been associated with increased maternal and neonatal complications. Race/ethnicity, low household income and poverty showed significant impact on infant mortality in Newark; investigating factors that influence unplanned out-of-hospital births at an inner-city hospital provides insight into clinical outcomes for at-risk mothers and their children. Methods: 66 unplanned out-of-hospital live births from January 2017 to December 2022 were compared with 72 randomly selected in-hospital live births, controlling for birth weight greater than 500g. Newborns with chromosomal abnormalities, stillbirths, non-singleton births, and congenital anomalies in neonates were excluded from analyses. Standard statistical tests (t-test, chi-square test of independence with Yates correction, and Fishers exact test) were applied in comparing in-hospital birth groups with the unplanned out-of-hospital births group. Results: Unplanned out-of-hospital newborns were more likely to be affected by low birth weight (OR=5.90, 95%CI [1.87, 18.6]), be born preterm (OR=4.84, 95CI% [1.67, 14.1]), and have a significantly lower average gestational age compared to the in-hospital group (p=4.13x10^-3). Hypoglycemia (OR=38.0, 95%CI [4.95, 291]), hypothermia (OR=35.5, 95% CI [4.62, 272]), and bradycardia (OR=15.58, 95% CI [0.86, 282]) were significantly associated with unplanned out-of-hospital births. Developmental delay, APGAR scores, neonatal mortality, and other neonatal complications were not significantly associated with birth location. Mothers of Black/African-American race were significantly more likely to have out-of-hospital births (OR=4.29, 95%CI [2.10, 8.74]). Mothers with unplanned out-of-hospital births were almost eight times more likely to have any substance-use-related ICD codes recorded in maternal charts (OR=7.98, 95%CI [2.22, 28.7]). Mothers with unplanned out-of-hospital births were more likely to receive less than appropriate prenatal care (OR=0.09, 95%CI [0.03, 0.26]) and no prenatal care at all (OR=5.44, 95%CI [1.71, 17.3]). Parity, maternal age at delivery, marital status, insurance, education, use of interpreting services, and employment status of the mother were not significantly associated with birth location. Conclusions: This study revealed multiple significant interconnected associations to UOHB that include insufficient prenatal care, substance use disorder, and demographic variables such as race/ethnicity. UOHB were significantly associated with preterm births, low birth weight, hypoglycemia, hypothermia and bradycardia. These findings emphasize the need for targeted interventions for at-risk populations to decrease the risk of preventable neonatal complications.