The method by which a baby was delivered is associated with how its immune system will respond to two key childhood vaccines, research suggests. Babies born naturally were found to have higher antibody levels, compared with those born via Caesarian section after receiving their jabs that protect against bacteria that cause lung infections and meningitis. Experts say the findings could help to inform conversations about C-sections between expectant mothers and their doctors, and shape the design of more tailored vaccination programs.