A technique not involving surgery is described for obtaining axenic (germ-free) newborn animals and human infants by decontamination immediately after birth. Three steps are involved: cleansing the perineal region of the mother with an iodinated bactericidal solution, washing the newborn with the same solution, and after the newborn has been placed in a sterile isolator, administering a single oral dose of an antibiotic mixture previously determined to be active against the fecal and vaginal flora of the mother. All of the newborn obtained by means of this technique, including 13 piglets, 2 lambs, and 4 human infants, were found to be axenic throughout their stay in the isolators. Four piglets obtained by the same technique, but without administration of antibiotic mixture, were found not to be axenic.This technique, as compared with methods of surgical delivery of axenic young, embodies a number of advantages. It is harmless to the mother and to the newborn, it is relatively inexpensive, and it obviates the risk of prematurity involved in elective surgical delivery before term.