O2060: National Trends in Gestational Age at Birth, Assisted Ventilation, Neonatal Intensive Care Admissions, and Antibiotic Exposure in the United States from 2016 to 2023

Background: The preterm birth rate [ < 37 weeks gestation age (GA)] increased by 12% from 2014 to 2022 in the United States (US) while births at 39-40 weeks and ≥41 weeks decreased by 6% and 28%, respectively, leading to a gradual decrease in GA at birth. However, there is limited data on the impact of these changes on short-term neonatal outcomes. We hypothesized that shifts in GA at birth will result in an increase in newborns with respiratory distress, neonatal intensive care unit (NICU) admissions, and antibiotic exposure. The primary objective was to evaluate the population-based temporal trends in these outcomes in the US between 2016 and 2023.

Methods: We conducted a retrospective, serial cross-sectional analysis of national livebirth data from the Wide-ranging Online Data for Epidemiologic Research from the Centers for Disease and Control and Prevention from 2016 through 2023. We excluded stillbirths. The exposure variable was calendar year. The outcomes of interest were the rate of NICU admissions, assisted ventilation, surfactant administration, and exposure to antibiotics, expressed as per 1,000 live births. Trend analysis was performed using linear regression, with a p-value < 0.05 considered statistically significant. The strength of the association between calendar year and the outcomes was assessed with correlation coefficient (R).

Results: Out of 29,874,337 livebirths from 2016 to 2023, 51.1% were male, 32% were delivered via cesarean section, and 97.5% had a 5-minute Apgar score ≥7. The average GA and birthweight were 38.4 weeks and 3254 gm, respectively. Diabetes, hypertension, and twin or higher order births complicated 8.3%, 10.5%, and 1.4% of pregnancies, respectively. Between 2016 and 2023, the average GA at birth decreased from 38.5 to 38.3 (p < 0.01, R=0.97) while average BW decreased from 3267 to 3240 gm (p < 0.001; R=0.97). NICU admission rates increased from 87 to 98 (p < 0.001, R=0.81). The overall rate of immediate assisted ventilation (per 1,000) increased from 39.2 to 63.2 (p < 0.001, R=0.99) while assisted ventilation >6 hours increased from 13.7 to 20.9 (p < 0.001; R=0.99). However, the change in surfactant replacement therapy was not significant (4.83 to 5.04; p=0.19). The rate of antenatal steroid administration (per 1000) also increased from 23.8 to 38.5 (p < 0.01, R=0.72). Neonatal exposure to antibiotics for suspected sepsis declined from 23 to 19 (p < 0.001; R=0.95) despite an increase in maternal chorioamnionitis from 15.3 to 17.6 per 1,000 (p=0.02; R=0.60).

Conclusion: Between 2016 and 2023, there were notable declines in GA and BW, alongside increases in NICU admissions and respiratory morbidity. These trends suggest potential increases in healthcare resource utilization. Decreased neonatal antibiotic exposure hints at shifts in infectious disease management or improved antibiotic stewardship. Further studies should investigate the drivers behind these changes.