Association of Rural and Frontier Residence with Very Preterm and Very Low Birth Weight Delivery in Nonlevel III NICUs

Abstract

Objective Delivery of very preterm and very low birth weight neonates (VPT/VLBW) in a nonlevel III neonatal intensive care unit (NICU) increases risk of morbidity and mortality. Study objectives included: (1) Determine incidence of VPT/VLBW delivery (<32 weeks gestational age and/or birth weight <1,500 g), in nonlevel III units in Colorado; (2) Evaluate the independent association between residence and nonlevel III unit delivery; (3) Determine the incidence of and factors associated with postnatal transfer. Study Design This retrospective cohort study used 2007 to 2016 Colorado birth certificate data. Demographic and clinical characteristics by VPT/VLBW delivery in level III NICUs versus nonlevel III units were compared using Chi-square analyses. Multivariable logistic regression was used to estimate the independent association between residence and VPT/VLBW delivery. Results 897 of 10,015 (8.96%) VPT/VLBW births occurred in nonlevel III units. Compared with infants born to pregnant persons in urban counties, infants born to those residing in rural (adjusted odds ratio or AOR 1.58, 95% confidence interval or CI 1.33, 1.88) or frontier (AOR 3.19, 95% CI 2.14, 4.75) counties were more likely to deliver in nonlevel III units and to experience postnatal transfer within 24 hours (rural AOR 2.24, 95% CI 1.60, 3.15; frontier AOR 3.91, 95% CI 1.76, 8.67). Compared with non-Hispanic whites, Hispanics were more likely to deliver VPT/VLBW infants in nonlevel III units (AOR 1.36, 95% CI 1.15, 1.61). Conclusion A significant number of VPT/VLBW neonates were born in nonlevel III units with associated disparities by race/ethnicity and nonurban residence. Key Points