Anti-smoking laws reduce asthma cases and preterm births

Anti-smoking laws are linked to reduced asthma cases in children and premature births, an international study suggests.

Researchers showed smoking bans in public places slashed the rates of both preterm births and childhood asthma attacks by 10 percent within a year of the law's enactment.

"Our study provides clear evidence that smoking bans have considerable public health benefits for perinatal and child health, and provides strong support for WHO recommendations to create smoke-free public environments on a national level," Dr. Jasper Been, lead study author from the Maastricht University Medical Center in the Netherlands, said in a statement.

Smoke-free laws cover currently only 16 percent of the world's population. Past studies reveal that 40 percent of children worldwide are regularly exposed to second-hand smoke, leading to respiratory disease and asthma attacks.

The World Health Organization (WHO) adds that tobacco kills 6 million people worldwide and 600,000 of those cases occur in non-smokers. To put it into perspective, at this rate, by 2030 the death toll will reach 8 million people annually, Reuters reports.

The analysis of 11 studies done in North America and Europe, published in the journal The Lancet, involved more than 2.5 million births and nearly 250,000 asthma exacerbations. It also found "a 5 percent decline in children being born very small for gestational age after the introduction of smoke-free laws," Been said.

"Smoking during pregnancy has been shown to have adverse effects on fetal development and pregnant women need to be informed of the risks and should be offered advice and support to help them give up," Professor Ronnie Lamont from the Royal College of Obstetricians and Gynecologists, not involved in the study, commented to BBC News.

Experts say children are particularly vulnerable to the negative effects of second-hand smoke because their lungs and immune systems are still developing, and these smoking bans have a positive impact on child health.

"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," study co-author Professor Aziz Sheikh concluded.