Background: The neonatal immune system is not completely developed until six months old. Newborns have elevated concentrations of maternal antibodies in the circulation. Newborns who are breastfed receive antibodies from breast milk. Probiotic species are "live organisms, which when supplied in sufficient amounts produce health benefits in the host", so they might protect high risk infants via increasing the barrier to translocation of pathogens and bacterial products across mucosa. Objective: The aim of the current work was to discuss factors, which influence the immunity in newborn infant exposed to infection and the current search for factors enhancing immunity in these babies. Methods: The following keywords were entered into on PubMed, Google Scholar, and Egyptian Knowledge Bank: Breast feeding, Complement system,Colostrum and Probiotics. Just the most recent or comprehensive study between March 2005 and July 2022, was included after the authors thoroughly examined references from the pertinent literature, including all the recognised studies and reviews. Papers written in a language other than English were disregarded since no sources for interpretation were discovered. Dissertations, conversations, conference abstract papers, and anything other than the primary scientific investigations had been disqualified. Conclusion: Early breastfeeding initiation within 30 minutes after birth promotes health, prevents diseases and decreases healthcare and costs. Babies must have exclusive breastfeeding in the initial six months after birth, which significantly decreased infant mortalities in developing countries. Probiotics decrease the incidence of necrotizing enterocolitis (NEC) in preterm and very low birth weight infant (VLBW) babies. Vaginal delivery strengthens both maternal and neonatal defense against infections.