Newborns who undergo vaginal delivery are exposed to maternal flora and bacteria in the environment, which facilitates the establishment of healthy intestinal flora (with bifidobacteria being dominant), allowing the maturation of the intestinal barrier function and reducing the chances of allergies; whereas cesarean delivery is aseptic, so that the colonization of the infant’s intestinal flora is delayed, affecting the development of the neonatal intestinal micro-ecosystem and thus the development of the infant’s early immune system, increasing the risk of infectious diseases and Allergy risk. Clinical studies have shown that bifidobacterial colonization of the intestinal tract differs between children delivered naturally and those delivered by cesarean section, with bifidobacterial colonization being delayed in children delivered by cesarean section, even up to 6 months after birth. Children delivered by cesarean section are at increased risk of asthma, hay fever, allergies, and respiratory infectious diseases after the first year of life, especially children born by cesarean section to mothers with a history of allergies are at a significantly increased risk of food allergy at 1-2 years of age and of asthma by the time they reach adulthood.