Stillbirths and the race-specific gap in neonatal death among extremely preterm births

In the extremely preterm period (ePTB; less than 28 weeks), non-Hispanic (NH) Black infants in the US show relatively lower risk of neonatal death than do NH white infants. Explanations for this survival advantage include higher levels of stillbirth among NH Black persons, which could leave behind hardier members of the conception cohort that survive to birth. We test this "high stillbirth" explanation in the US and focus on NH Black singleton ePTB males given their large survival advantage. We applied time-series methods to 288 monthly conception cohorts (1995-2018 US fetal, birth, and neonatal death records) for NH Black and NH white singletons in the ePTB range (N = 473,472). We specified positive monthly outliers in male relative to female NH Black stillbirths in the ePTB range to gauge high NH Black male stillbirths. NH Black male ePTB singleton infants show a stronger neonatal survival advantage (relative to NH whites) for cohorts with high NH Black male stillbirth (4.4 fewer deaths per 100 live births, standard error = 1.3, p < .001). Cohort variation in fetal loss, as measured by high NH Black male stillbirth, may explain a portion of the counterintuitive racial/ethnic patterns in live birth mortality among extremely preterm births.