Smoking bans are associated with a "consistent pattern
of reduction in the risk of preterm delivery," finds a new study. The
study supports the notion that smoking bans have public health benefits from
early life.
It is well established that smoking during pregnancy impairs
the growth of an unborn child and shortens gestation. Exposure to second-hand
smoke has also been found to affect birth outcomes, yet little is known about
the impact of recent smoke-free legislation on birth weight and preterm birth.
So a team of researchers, lead by Dr Tim Nawrot from Hasselt
University, investigated whether recent smoking bans in Belgium were followed
by changes in preterm delivery. In Belgium, smoke-free legislation was
implemented in three phases (in public places and most workplaces in January
2006, in restaurants in January 2007, and in bars serving food in January
2010).
The researchers analysed 606,877 live, single-born babies
delivered at 24-44 weeks of gestation in Flanders from 2002 to 2011. Preterm
birth was defined as birth before 37 weeks.
They found reductions in the risk of preterm birth after the
introduction of each phase of the smoking ban. No decreasing trend was evident
in the years or months before the bans.
The results show a reduction in the risk of preterm births of 3.13% on 1 January 2007 (ban on smoking in restaurants), and a further reduction in the risk of 2.65% after 1 January 2010 (ban on smoking in bars serving food). These changes could not be explained by several other factors -- both at the individual level, such as mother's age and socioeconomic status -- and at the population level, such as changes in air pollution and influenza epidemics.
Given that even a mild reduction in gestational age has been
linked in other studies to adverse health outcomes in early and later life, our
study has important public health implications, say the authors.
"Our study shows a consistent pattern of reduction in
the risk of preterm delivery with successive population interventions to
restrict smoking. It supports the notion that smoking bans have public health
benefits even from early life. More and more countries in Europe are adopting
stricter legislation on smoking in public places. These results underscore the
public health benefit of smoking ban policies."
Story Source:
The above post is reprinted from materials provided by
BMJ-British Medical Journal. Note: Materials may be edited for content and
length.
Journal Reference:
B. Cox, E. Martens, B. Nemery, J. Vangronsveld, T. S.
Nawrot. Impact of a stepwise introduction of smoke-free legislation on the rate
of preterm births: analysis of routinely collected birth data. BMJ, 2013; 346
(feb14 3): f441 DOI: 10.1136/bmj.f441
