Banning smoking in public places has helped to cut premature births by 10 per cent, new research shows.
The study of data from parts of North America and Europe where smoking bans have been introduced also showed a 10 per cent fall in hospital attendance for childhood asthma attacks.
The findings reveal that the impact of anti-smoking laws varies between countries but overall the effect on child health around the world is very positive.
Laws that prohibit smoking in public places, such as bars, restaurants and work places, are already proven to protect adults from the health threats associated with passive smoking.
This is the first comprehensive study to look at how anti-smoking laws in different countries and areas are affecting the health of children living in those regions. It is published today in the journal The Lancet.
Less than one sixth of the world's population is currently protected by anti-smoking laws. As a result, 40 per cent of children around the world are regularly exposed to second hand smoke, which claims an estimated 160,000 young lives each year and causes significantly more disability.
Passive smoking can cause babies to be stillborn or born prematurely and is linked to birth defects, asthma and lung infections. Studies have also suggested that being exposed to second hand smoke during childhood may have long term health implications, contributing to the development of chronic diseases like heart disease and diabetes in later life.
The study was led by the University of Edinburgh together with researchers from Maastricht University, Hasselt University, Harvard Medical School and Brigham and Women's Hospital. The researchers looked at over 2.5 million births and almost 250,000 hospital attendances for asthma attacks.
Lead researcher, Dr Jasper Been of the University of Edinburgh's Centre for Population Health Sciences, said: "Our research shows that smoking bans are an effective way to protect the health of our children. These findings should help to accelerate the introduction of anti-smoking legislation in areas not currently protected."
Professor Aziz Sheikh, Co-Director of the Centre for Population Health Sciences at the University of Edinburgh, said: "This research has demonstrated the very considerable potential that smoke-free legislation offers to reduce preterm births and childhood asthma attacks. The many countries that are yet to enforce smoke-free legislation should in the light of these findings reconsider their positions on this important health policy question."