According to how the other half lives, how did the living conditions in buildings in the slums affect babies?

How the other half lives is a book about the terrible housing conditions in the slum areas of New York written by Jacob Riis in 1890. The living conditions in these slums were very terrible and the spaces available to each family were extremely small, because of these unhealthy conditions, babies were often negatively affected and this usually results in sickness and sometimes death.