Intensity of perinatal care for extremely preterm infants: outcomes at 2.5 years

Abstract

Objective: To examine the association between intensity of perinatal care and outcome at 2.5 years' corrected age (CA) in extremely preterm (EPT) infants (<27 weeks) born in Sweden during 2004-2007.

Methods: A national prospective study in 844 fetuses who were alive at the mother's admission for delivery: 707 were live born, 137 were stillborn. Infants were assigned a perinatal activity score on the basis of the intensity of care (rates of key perinatal interventions) in the infant's region of birth. Scores were calculated separately for each gestational week (gestational age [GA]-specific scores) and for the aggregated cohort (aggregated activity scores). Primary outcomes were 1-year mortality and death or neurodevelopmental disability (NDI) at 2.5 years' CA in fetuses who were alive at the mother's admission.

Results: Each 5-point increment in GA-specific activity score reduced the stillbirth risk (adjusted odds ratio [aOR]: 0.90; 95% confidence interval [CI]: 0.83-0.97) and the 1-year mortality risk (aOR: 0.84; 95% CI: 0.78-0.91) in the primary population and the 1-year mortality risk in live-born infants (aOR: 0.86; 95% CI: 0.79-0.93). In health care regions with higher aggregated activity scores, the risk of death or NDI at 2.5 years' CA was reduced in the primary population (aOR: 0.69; 95% CI: 0.50-0.96) and in live-born infants (aOR: 0.68; 95% CI: 0.48-0.95). Risk reductions were confined to the 22- to 24-week group. There was no difference in NDI risk between survivors at 2.5 years' CA.

Conclusions: Proactive perinatal care decreased mortality without increasing the risk of NDI at 2.5 years' CA in EPT infants. A proactive approach based on optimistic expectations of a favorable outcome is justified.

Keywords: cohort study; extremely preterm infants; mortality rates; neurodevelopmental outcome.