To categorize newborn infants in Hamilton County, Ohio by late pregnancy fetal opioid exposure status and to assess their first-year healthcare utilization.

We used a population-based cohort of 41 136 live births from 2014-2017 and analyzed healthcare encounters in the first year of life from electronic health records. We prospectively assessed for the presence of opioids in maternal urine collected at delivery and for a diagnosis of newborn neonatal abstinence syndrome (NAS). At birth, infants were classified as unexposed to opioids, exposed to opioids and diagnosed with NAS, or subclinically exposed to opioids (exposure that did not result in NAS).

The prevalence of newborn opioid exposure was 37 per 1000 births. The duration of the hospital birth encounter was significantly longer for infants with subclinical exposure compared with unexposed infants (10% increase; 95% CI, 7%-13%). However, duration for infants with subclinical exposure was shorter compared to those with NAS. Neither subclinical exposure nor NAS was associated with total emergency department visits. Subclinical exposure was associated with increased odds of having at least 1 hospitalization in the first year. However, the total length of stay for hospitalizations was 82% that of the unexposed group (95% CI, 75%-89%). Infants with NAS had a 213% longer total length of stay compared with the unexposed group (95% CI, 191%-237%).

Subclinical and overt opioid exposure among newborn infants was associated with increased first-year healthcare utilization. From 2014 to 2017, this cost the Hamilton County healthcare system an estimated $1 109 452 for longer birth encounters alone.