Changes in Neonatal Morbidity and Neonatal Care Practices of Infants Born Very Preterm in the Netherlands in the 1980s and 2000s

This study evaluates changes in neonatal morbidity and care practices of very preterm (VP) infants born in the Netherlands in the 1980s and 2000s and analyzes whether these changes were associated with infant and maternal characteristics, risk factors during pregnancy, and obstetrical outcomes.The community-based cohorts of POPS (1983) and LOLLIPOP (2002-03) provided perinatal data for the study. The analysis enrolled 1,228 participants born VP (before 32 weeks of gestation) and survived to 2 years of age. In 2003, mothers were on average 3.3 years older when giving birth than in 1983. Multiple birth rates increased by 50% and significantly more parents had higher education. Prevalence of severe IVH and sepsis decreased in VP infants between 1983 and 2003. LOLLIPOP infants received more often continuous positive airway pressure (CPAP), mechanical ventilation, and caffeine therapy than POPS infants. Antenatal corticosteroids and surfactant therapy were introduced only in the LOLLIPOP cohort. In 2002-03, length of stay in the NICU was reduced by 57% in LOLLIPOP (median 16 days) compared to POPS (median 38 days). LOLLIPOP infants also spent 11 days less total time in hospital after birth (median 54 days). This is a reduction of 17% compared to POPS (median 65 days). Differences persisted after adjustment for infant and maternal characteristics, risk factors during pregnancy, and obstetrical outcomes.Conclusions: Infant and mother characteristics changed considerably as well as obstetric and neonatal care practices. Outcomes of several severe neonatal morbidities improved. Length of NICU and hospital stay were significantly shorter in the 2000s.