Does How You Deliver Your Baby Affect Her Immune System?

Researchers from the University of Copenhagen/Faculty of Health and Medical Science in Copenhagen, Denmark, have been studying baby mice to see whether the way in which a baby is delivered has an impact on the development of her immune system. They report that “pups” delivered by Caesarean section (C-Section) developed a lower number the types of cells that strengthen the immune system than the babies who were born vaginally.

Their conclusion: Vaginal childbirth may boost a baby’s immune system, because that baby will be exposed to more of the mother’s bacteria; in turn, bacteria exposure may help tip off the newborn baby’s immune system to distinguish between its own harmless molecules and potentially harmful foreign molecules.


The mice delivered via C-Section showed a lower number of the cells that play an important role in preventing reactive immune cells from responding to molecules from their own bodies, from diet, and from harmless intestinal diseases. This is an important finding, since autoimmune diseases including Crohn’s disease, Type One Diabetes, and many allergies are all characterized by an overreaction of the immune system.

Researchers published their findings recently in the Journal of Immunology. The next step in the ongoing study will be clinical trials to see whether methods can be developed to strengthen the immune systems of newborns, particularly those who may be predisposed to a variety of autoimmune diseases.