Germinal matrix hemorrhage: intraventricular hemorrhage in very-low-birth-weight infants: the independent role of inherited thrombophilia.

BACKGROUND AND PURPOSE The etiology of germinal matrix hemorrhage-intraventricular hemorrhage (GMH-IVH) is multifactorial and the role of genetic polymorphisms is unclear. The aim of this prospective study was to evaluate prothrombotic genetic mutations as independent risk factors for the development of all grades of GMH-IVH in very-low-birth-weight infants. METHODS The presence of both factor V Leiden and prothrombin gain-of-function gene mutations were prospectively assessed in 106 very-low-birth-weight infants. Infants with GMH-IVH were compared to those without GMH-IVH according to genetic and clinical characteristics. RESULTS Twenty-two out of 106 infants had GMH-IVH develop (20.7%). Infants with GMH-IVH had significantly lower gestational ages and birth weights. In the multivariate Poisson regression model, the prevalence of GMH-IVH appeared to be inversely related to gestational age, with a risk ratio of 0.83 (95% CI, 0.72-0.97; P=0.02) per week. Risk ratio of GMH-IVH for carriers of either prothrombotic mutation was 2.65 (95% CI, 1.23-5.72; P=0.01), similar to the risk ratio associated with need for resuscitation at birth (2.30; 95% CI, 1.02-5.18; P=0.04). CONCLUSIONS Very-low-birth-weight infants who are carriers for either prothrombotic mutations are at increased risk for development of GMH-IVH. Genetic factors act as independent risk factors of the same magnitude as other known risk factors.