Scotland was the first country in the UK to implement a public place smoking ban, back in March of 2006. Now researchers have gone back and looked at a number of birth complications, and seen them drop precipitously since the legislation came into effect.

Specifically, the researchers were tracking preterm and underweight births from January 1996 to December 2009. They found that since the law kicked in, the number of complications has lowered significantly. Even adjusted for other variables, preterm deliveries dropped 11.7% (as much as 17.4% in moderately and extremely preterm); spontaneous preterm labor fell 11.3%; low birth weight dropped 9.9%; and babies born either small or very small for their gestational age lowered 4.5% and 8% respectively.

What's interesting, and perhaps the rub of this study, is that even though the rate of mothers smoking did drop from 25.4% to 18.8%, the improvement in complications was universal. Even with mothers who had never smoked, the rates improved.

So while workplace smoking bans are still being hotly debated in parts of the USA, other nations are already observing the long term health benefits.