INTRODUCTION:Survival has improved among very preterm born infants, but improved treatment strategies might be associated with increasing rates of neonatal morbidity. The aim of this study was to assess survival and major morbidities among very and extremely preterm born infants treated in a Danish neonatal intensive care unit. METHODS:This was an observational cohort study including very preterm infants (gestational age (GA) < 32 weeks) born between year 2000 and 2013. Because of changes in three standard treatments from 2008, we aimed to compare survival and major neonatal morbidity between two birth-year periods: 2000-2007 and 2008-2013. RESULTS:The overall survival rate increased from 81.6% to 85.0%. In GA group 26-27 weeks, survival increased from 65% to 89% (p = 0.02). A total of 31/412 (7.5%) in the first time period and 30/280 (10.7%) in the second time period were diagnosed with bronchopulmonary dysplasia. No difference was found for necrotising entrocolitis or intraventricular haemorhage. Antibiotic treatment was similar in the two time periods, though antibiotic treatment for suspected clinical infection increased in the second time period (35.1% versus 44.1%). CONCLUSIONS:We found a significant increase in the survival rate in GA group 26-27 weeks, but no significant increase in any major morbidity when comparing the two time periods. TRIAL REGISTRATION:not relevant. FUNDING:none.