Perinatal Resources and Wildfire Smoke.

Abstract

Background: Pregnant people and infants are vulnerable to wildfire smoke. However, the availability of perinatal resources in communities impacted by smoke is unknown.

Objective: Describe perinatal resources in counties prone to wildfire smoke.

Research study design: Smoke data came from the Hazard Mapping System and perinatal resources were gathered from various sources. Choropleth maps described the geographic distribution of smoke. Unadjusted associations and multivariable regressions compared perinatal resource levels by smoke risk. Subgroup analysis of the most rural counties was conducted.

Subjects: Counties in the contiguous United States (n=3108) during the 2016-2020 period.

Measures: Relative smoke risk was defined as the bottom, middle, and top third of the average annual smoke-days distribution. Perinatal resources included driving distance to the nearest maternity care hospital and NICU, the volume and geographic isolation of the nearest maternity care hospital, and county-based measures of OB-GYN and family medicine physicians.

Results: Average annual smoke-days ranged from 3.8 (SD=2.0) in low-risk to 15.3 (SD=5.5) in high-risk counties. Compared with low-risk counties, high-risk counties had fewer OB-GYNs per 10,000 births (-32.2, 95% CI: -45.7 to -20.6; P<0.001) and were farther to the nearest maternity hospital (10.1 miles, 95% CI: 8.7-11.5; P<0.001). High-risk counties were also farther to the nearest NICU. Associations were not explained by sociodemographics and were observed in the subset of the most rural counties.

Conclusions: Communities prone to wildfire smoke often lack geographic access to the health care resources needed to treat pregnant people and infants in a timely manner.