Variability in very preterm stillbirth and in-hospital mortality across Europe

Background: Stillbirth and in-hospital mortality rates associated with very preterm (VPT) births vary widely across Europe. International comparisons of these rates are complicated by a lack of standardised data collection, differences in definitions, registration and reporting. This study aims to determine what proportion of the regional variation in stillbirth and inhospital VPT mortality rates persists after adjustment for population demographics, case-mix and timing of death. Methods: Standardised data collection for a geographically defined prospective cohort of VPT birth (22+0-31+6 weeks of gestation) across 16 regions in Europe. Crude and adjusted stillbirth and in-hospital mortality rates for VPT infants were calculated by timing of death using multinomial logistic regression models. Results: The stillbirth and in-hospital mortality rate for VPT births was 27.7% (range 19.9%- 35.9% by region). Adjustment for maternal and pregnancy characteristics had little impact on the variation. Addition of infant characteristics reduced the variation of mortality rates by about one fifth (4.8%-3.9%). The standard deviation for deaths <12 hours was reduced by one quarter but did not change for deaths ≥12 hours following risk adjustment. Conclusion: In terms of the regional variation in overall VPT mortality, over four fifths of the variation could not be accounted for by maternal, pregnancy and infant characteristics. Investigation of timing of death showed that these characteristics only accounted for a small proportion of the variation in VPT deaths. These findings suggest that there may be an inequity in the quality of care provision and treatment for VPT infants across Europe.