Logistic regression analysis including the variables gestational age, 5 minute Apgar score, intubation, incidence of a patent ductus arteriosus, hematocrit, and VKORC1-genotype revealed significant contributions of gestational age (OR 0.93 per day (95% CI 0.89-0.98), p = 0.004), and VKORC1 -1639A carrier status (OR 0.20 (95% CI 0.05-0.80), p = 0.024) to the individual IVH-risk. The gene discussed is VKORC1; the disease is Patent ductus arteriosus.