The improvement in child survival is attributed to many things, but it may be a mix of vaccinations, less indoor air pollution, much better hygiene, better nutr

The improvement in child survival is attributed to many things, but it may be a mix of vaccinations, less indoor air pollution, much better hygiene, better nutrition, and perhaps just better parenting. (People have had some very peculiar ideas on how to care for and raise children; I wouldn't be surprised if in hindsight our distant descendants consider us woefully inadequate in that regard too.) Most of the progress, in absolute terms, with reducing maternal mortality and the infant/toddler death rate in the industrialized countries was actually made before antibiotics were developed, in the late 19th / early 20th centuries. In England in 1851 about 26% of children died before the age of 5, falling to 23% in 1891, 19% in 1911, 11% in 1921, 9% in 1931, and 7% in 1941 (and then we're in the antibiotics era).