timelets

Instead of mother’s milk, babies were nourished with cow-milk or pap, often prepared by chewing bread and feeding it to the baby through a tube. Given the deficient storage of the food and the breeding of germs in the utensils, contagion in the infants was inevitable. In Berlin in 1885, mortality was seven times as high among artificially nursed babies as among the breastfed. Knowledge about nursing and caring improved but still in 1910 the difference was 4.4 times (Vögele 1998, p. 82).
By contrast, where infant mortality was the lowest, in Ireland, Scotland, and Scandinavia, breastfeeding was overwhelmingly the dominant practice (Newman 1906, pp. 221ff.).
...
Improved care of infants was also pushed by infant welfare centers, set up in Germany after 1900, by British Medical Health Officers, and by doctors such as George Newman, who in 1906 published the remarkable book Infant Mortality. A Social Problem (Kintner 1985; on Newman, see Galley 2006 and Woods 2006).

In the beginning of the 20th century, Germany and Russia had the highest infant mortality rates in Europe. I wonder what infant mortality was in the Soviet Union during the industrialization period (1929 - 1940). The stats are hard to find.