The lives of more than 1,400 babies were saved in the four years after Britain banned smoking in enclosed public places, according to an analysis of ten million births.
Scientists said that after the legislation came into force in 2007 there was an immediate 8 per cent drop in stillbirths and neonatal deaths.
However, the claim proved controversial, with others pointing out that mortality was already declining.
Researchers from Edinburgh University looked at all the babies born in England in the years before and after the ban on smoking in pubs, offices and other public places took effect.
In a study published in the journal Nature Scientific Reports, they then extrapolated the trends before the law change, to estimate how many babies would have