Changes in perinatal management and outcomes of extremely preterm infants born below 26 weeks of gestation in a tertiary referral hospital in Sweden: Comparison between 2004-2007 and 2012-2016.

ABSTRACT

INTRODUCTION: Perinatal management of extremely preterm births in Sweden has changed toward active care from 22-23 gestational weeks during the last decades. However, considerable regional differences exist. This study evaluates how one of the largest perinatal university centers has adapted to a more active care between 2004-2007 and 2012-2016 and if this has influenced infant survival. MATERIAL AND METHODS: In this historical cohort study, women admitted with at least one live fetus and delivered at 22-25 gestational weeks (stillbirths included) at Karolinska University Hospital Solna during April 1, 2004-March 31, 2007, and January 1, 2012-December 31, 2016, were compared regarding rates of obstetric and neonatal interventions, and infant mortality and morbidity. Maternal, pregnancy and infant data from 2004-2007 were obtained from the Extreme Preterm Infants in Sweden Study while data from 2012-2016 were extracted from medical journals and quality registers. The same definitions of interventions and diagnoses were used for both study periods. RESULTS: A total of 106 women with 118 infants during 2004-2007 and 213 women with 240 infants during 2012-2016 were included. Increases between the study periods were seen regarding cesarean delivery (overall rate 14% [17/118] during 2004-2007 vs. 45% [109/240] during 2012-2016), attendance of a neonatologist at birth (62% [73/118] vs. 85% [205/240]) and surfactant treatment at birth in liveborn infants (60% [45/75] vs. 74% [157/211]). Antepartum stillbirth rate decreased (13% [15/118] vs. 5% [12/240]) and the proportion of live births increased (80% [94/118] vs. 88% [211/240]) while 1-year survival (64% [60/94] vs. 67% [142/211]) and 1-year survival without major neonatal morbidity (21% [20/94] vs. 21% [44/211]) among liveborn infants did not change between the study periods. At 22 gestational weeks, interventions rates were still low during 2012-2016, most obvious regarding antenatal steroid treatment (23%), attendance of a neonatologist (51%), and intubation at birth (24%). CONCLUSIONS: Both obstetric and neonatal interventions at births below 26 gestational weeks increased between 2004-2007 and 2012-2016 in this single center study; however, at 22 gestational weeks they were still at a low level during 2012-2016. Despite more infants being born alive, 1-year survival did not increase between the study periods.