Extending the Benefits of a Smoke-Free Environment to Those Still In Utero

Both maternal smoking and exposure to second-hand smoke affect pregnancy outcomes (JW Womens Health Apr 9 2009). To determine whether legislation to limit public smoking can lower risk for preterm delivery, investigators analyzed data on >606,000 singleton live births at 24 to 44 weeks' gestation in Flanders from 2002 through 2011. Smoke-free legislation in Belgium was implemented in phases, with all public places and workplaces (except for restaurants) becoming smoke-free in January 2006, restaurants becoming smoke-free in January 2007, and bars serving food becoming smoke-free in January 2010; thus, it was possible to assess changes in rates of spontaneous preterm delivery over time.

Overall, 7.2% of spontaneous deliveries occurred before 37 weeks' gestation. The preterm birth rate was relatively stable at 7.4% before the first smoke-free legislation, then began to fall during the year thereafter. The largest drops in preterm birth rates followed the smoking bans in restaurants and bars serving food, and by 2011, the rate was 6.8%. In all, the declines during the 5 years after 2007 corresponded to a reduction of 6 preterm births per 1000 deliveries.