Jensen AK, et al. - In this study, authors identified the time period in postnatal development during which thrombocytopenia and the subsequent development of severe retinopathy of prematurity (ROP) were associated. They noted that thrombocytopenia from birth through postmenstrual age (PMA) weeks 34 was related to subsequent severe ROP. In infants at risk for ROP, this time period corresponded to a period of poor retinal vascular growth, thereby suggesting a possible proangiogenic effect of platelets in normal retinal vascular development.