Designing prophylactic strategies for newborns requires understanding of the factors that contribute to immunity and resistance to infection. We analyzed 1,892,035 mother-newborn pairs in which both the mother and newborn were observed continuously for at least one year before and after birth. As part of this study, we considered maternal exposures to infections and immune disorders during pregnancy, exposures to anti-infection medications by both mother and newborn, as well as the newborn's delivery type and reported complications. According to our analyses, infection rates and immune disorder rates were over-dispersed among newborns. The most consequential factors predicting newborns' immune health were preterm birth, with 276.3% and 193.9% risk increases for newborn bacterial infections. Newborn anti-infective prescriptions were associated with considerable increases in risk of diseases affecting immune health, while maternal prescriptions were associated with fewer outcomes and with mixed signs. The Cesarean section mode of delivery, the mother's age, the sex of the newborn, and the mother's exposure to infections all showed significant but smaller effects on the newborn's immune health. Female newborn appeared to be better protected against diseases with immune system etiology, except for miscellaneous infections.
Keywords: Newborn immunity; immune system disbalance risk factors; maternal factors affecting child health; susceptibility to infections.