Extremely premature (BW<1250g) infants are at high risk for morbidity and mortality. Own mother's colostrum (OMC) and milk (OMM) protect against neonatal morbidity and are rich in immune factors which may provide immunostimulatory effects when administered oropharyngeally to extremely premature infants during the first weeks of life. This 5-year placebo-controlled, double-blind randomized controlled trial will evaluate the safety, efficacy and health outcomes of oropharyngeal administration of OMC/OMM in a sample of 622 (total patients enrolled) extremely premature infants with the following aims: Aim 1. To determine if oropharyngeal administration of OMC/OMM to extremely premature infants will reduce the risk of late-onset sepsis or death as the primary outcome, and necrotizing enterocolitis and ventilator-associated pneumonia as pre-planned secondary outcomes. Aim 2: To determine if extremely premature infants who receive OMC/OMM via the oropharyngeal route have a shorter time to reach full enteral feeds and a shorter length of hospital stay. Aim 3: To determine if oropharyngeal administration of OMC/OMM will have immunostimulatory effects for extremely premature infants, as measured by (A) enhancement of gastrointestinal (fecal) microbiota, (B) improvement in antioxidant defense maturation or reduction of pro-oxidant status, and (C) maturation of immunostimulatory effects as measured by changes in urinary lactoferrin. Results will confirm whether extremely premature infants demonstrate a host-immune response to this intervention and whether there is a beneficial effect on common morbidities in these high risk patients.