(NEW YORK) -- A study published in the British Medical Journal found that the frequency of premature births dropped in Belgium as the result of a public smoking ban.
The ban was rolled out in three stages, and after each phase, the rate of premature births dropped. The ban's first phase prohibited smoking in public places and workplaces and was instituted in 2006. Restaurants banned smoking in 2007, and bars serving food followed suit in 2010.
The study, conducted at Hasselt University in Belgium, was based on 600,000 births between 2002 and 2011 and defined premature birth as birth before 37 weeks. Researchers found that the rate of premature births fell after each phase of the ban.
The most notable drops were after the second and third stages, which saw the premature birth rate fall by about 3 percent each time.
A Scottish study in 2012 found a similar pattern, strengthening the theory that public smoking bans help to cut the number of children born prematurely. Separate studies have concluded that secondhand smoke has an impact on pre-term birth rate.
The study supports the belief that public smoking bans may help take some of the risk out of pregnancy.
Public smoking has been banned in 28 states as well as a number of other cities and counties.
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