Intraventricular hemorrhage (IVH) and periventricular leukomalacia (PVL) are brain lesions that commonly occur in preterm infants and are well-recognized major contributors to long-term brain injury and related disabilities later in life. Despite its prevalence, long term consequences, and enormous medical and social costs, mechanisms of IVH and optimal strategies to prevent or treat its occurrence are poorly defined, especially for extremely premature infants. Only one medical therapy, prophylactic indomethacin during the first 3 days of life, has been shown to prevent or decrease the severity of IVH in preterm infants, but its use is limited by toxic side effects and debatable effects on long-term outcomes. Several small studies and case reports suggest that delayed umbilical cord-clamping (DCC) may also decrease the incidence of IVH in premature infants, but thus far these trials have indomethacin treatment mixed within their cord clamping protocols. We will therefore conduct a randomized, blinded investigation of 4 treatment groups: 1) Control (no intervention); 2) DCC alone; 3) Prophylactic indomethacin alone; 4) Combination of DCC/indomethacin, with respect to survival, IVH or PVL incidence and severity, neurodevelopmental outcomes, and relevant mechanistic effects. Our Specific Aims are: Aim 1) Compare efficacy and safety of prophylactic indomethacin, DCC, and their combination, in affecting the incidence and severity of IVH/PVL in infants <28wks gestational age (primary outcome measure of 'fraction of survivors with no severe IVH or PVL' among the 4 groups), and longer term neurocognitive function; Aim 2) Investigate mechanistic effects of prophylactic indomethacin, DCC, and their combination in infants less than 28wks gestational age (blood volume/circulatory status, inflammatory stress, progenitor cells); and Aim 3) Determine relationships between clinical outcomes and mechanistic measurements among treatment groups (n=400 total cases). With the steady rise in extreme prematurity births and clear links of IVH to long-term disabilities there is a need to improve care for these patients. This multi-disciplinary project addresses an important medical problem for an understudied patient population, where the current practice has clear limitations.