RESUMEN
BACKGROUND: Intraventricular hemorrhage (IVH) is a serious problem in preterm infants. Brazilian national data are unknown. OBJECTIVE: To evaluate the incidence and temporal trend of IVH in very low birth weight (VLBW) preterm infants of 18 centers of the Brazilian Network on Neonatal Research. STUDY DESIGN: National prospective multicenter cohort study including inborn VLBW preterm infants aged 230/7- 336/7 weeks' gestation, admitted between 2013 and 2018. The center with the mean incidence rate was used as reference. We applied two adjustments models using perinatal variables, and perinatal + neonatal diseases. RESULTS: Of 6,420 infants, 1951/30.4% (range 27.1-33.8%) had IVH and the disease showed a significant trend towards an overall increase in incidence over time (p = 0.003), especially in three centers. Severe IVH (grade III or IV) occurred in 32.2% (range 29.2-34.5%) of those affected by IVH, with a stable incidence. After adjustments for perinatal variables, the differences persisted among centers: for global IVH, 7 centers had significantly lower rates (OR ranging from 0.31 to 0.62), and 2 presented rates higher than the reference center (OR ranging from 2.00 to 12.46) for severe HIV. Considering perinatal and neonatal variables, 6 centers had significantly lower rates (OR ranging from 0.36 to 0.60) for global IVH than the reference center and 3 had statistically higher rates (OR 1.72, 1.86 and 11.78) for severe forms. CONCLUSION: The incidence rate of IVH in this Brazilian cohort was high and it revealed an increasing trend towards over time. The severe IVH rate was also worrisome.