On top of all that, about four women in every ten are given antibiotics during delivery, which means that doctors are declaring war on babies’ microbes just as they are acquiring them. We’ve no idea what consequences this has for their long-term health, but it’s unlikely to be good. There are concerns already that certain beneficial bacteria are becoming endangered. B. infantis, an important microbe in mother’s milk, is found in up to 90 percent of children in developing countries but as little as 30 percent in the developed world.
