Smoking Ban and Pregnancy Complications: New Evidence

In-home Smoking in Households with Women of Reproductive Age in Nepal: Does Women's Empowerment Matter?

Authors examined the prevalence and predictors of in-home smoking in households with women of reproductive age. They analyzed data from 9,837 ever married women from 2011 Nepal Demographic Health Survey. About 17 percent of women and 66 percent of their husbands smoked and 58 percent of the women lived in homes that permitted in-home smoking. About 6 percent of the women were pregnant and 42 percent had given birth within the past five years. In-home tobacco use was equally prevalent in homes with and without young children and irrespective of women's pregnancy status. Husband's use of tobacco doubled the odds of in-home smoking (odds ratio [OR] = 2.36; 95% confidence interval [CI] = 1.52-3.69) and wife's use of tobacco quadrupled the odds of in-home smoking controlling for other factors (OR = 3.94; 95% CI = 3.30-4.70). In addition, employed women were 39 percent more likely to allow in-home smoking than their unemployed counterparts (OR = 1.39; 95% CI = 1.19-1.63). Protective factors against in-home smoking were women's education, intrahousehold decision-making ability, household wealth, and urban residence. To reduce in-home smoking, social workers should increase awareness about the adverse consequences of secondhand smoke by providing counseling services to male and female tobacco users.

Effect of smoke-free legislation on perinatal and child health: a systematic review and meta-analysis

BACKGROUND

Smoke-free legislation has the potential to reduce the substantive disease burden associated with second-hand smoke exposure, particularly in children. We investigated the effect of smoke-free legislation on perinatal and child health.

METHODS

We searched 14 online databases from January, 1975 to May, 2013, with no language restrictions, for published studies, and the WHO International Clinical Trials Registry Platform for unpublished studies. Citations and reference lists of articles of interest were screened and an international expert panel was contacted to identify additional studies. We included studies undertaken with designs approved by the Cochrane Effective Practice and Organisation of Care that reported associations between smoking bans in workplaces, public places, or both, and one or more predefined early-life health indicator. The primary outcomes were preterm birth, low birthweight, and hospital attendances for asthma. Effect estimates were pooled with random-effects meta-analysis. This study is registered with PROSPERO, number CRD42013003522.

FINDINGS

We identified 11 eligible studies (published 2008-13), involving more than 2·5 million births and 247,168 asthma exacerbations. All studies used interrupted time-series designs. Five North American studies described local bans and six European studies described national bans. Risk of bias was high for one study, moderate for six studies, and low for four studies. Smoke-free legislation was associated with reductions in preterm birth (four studies, 1,366,862 individuals; -10·4% [95% CI -18·8 to -2·0]; p=0·016) and hospital attendances for asthma (three studies, 225,753 events: -10·1% [95% CI -15·2 to -5·0]; p=0·0001). No significant effect on low birthweight was identified (six studies, >1·9 million individuals: -1·7% [95% CI -5·1 to 1·6]; p=0·31).

INTERPRETATION

Smoke-free legislation is associated with substantial reductions in preterm births and hospital attendance for asthma. Together with the health benefits in adults, this study provides strong support for WHO recommendations to create smoke-free environments.

FUNDING

Thrasher Fund, Lung Foundation Netherlands, International Paediatric Research Foundation, Maastricht University, Commonwealth Fund.

Smoking ban and small-for-gestational age births in Ireland

Background

Ireland introduced a comprehensive workplace smoke-free legislation in March, 2004. Smoking-related adverse birth outcomes have both health care and societal cost implications. The main aim of this study was to determine the impact of the Irish smoke-free legislation on small-for-gestationa- age (SGA) births.

Methods and Findings

We developed a population-based birthweight (BW) percentile curve based on a recent study to compute SGA (BW <5^th percentile) and very SGA (vSGA - BW<3^rd percentile) for each gestational week. Monthly births born between January 1999 and December 2008 were analyzed linking with monthly maternal smoking rates from a large referral maternity university hospital. We ran individual control and CUSUM charts, with bootstrap simulations, to pinpoint the breakpoint for the impact of ban implementation ( = April 2004). Monthly SGA rates (%) before and after April 2004 was considered pre and post ban period births, respectively. Autocorrelation was tested using Durbin Watson (DW) statistic. Mixed models using a random intercept and a fixed effect were employed using SAS (v 9.2). A total of 588,997 singleton live-births born between January 1999 and December 2008 were analyzed. vSGA and SGA monthly rates declined from an average of 4.7% to 4.3% and from 6.9% to 6.6% before and after April 2004, respectively. No auto-correlation was detected (DW = ∼2). Adjusted mixed models indicated a significant decline in both vSGA and SGA rates immediately after the ban [(−5.3%; 95% CI −5.43% to −5.17%, p<0.0001) and (−0.45%; 95% CI: −0.7% to −0.19%, p<0.0007)], respectively. Significant gradual effects continued post the ban periods for vSGA and SGA rates, namely, −0.6% (p<0.0001) and −0.02% (p<0.0001), respectively.

Conclusions

A significant reduction in small-for-gestational birth rates both immediately and sustained over the post-ban period, reinforces the mounting evidence of the positive health effect of a successful comprehensive smoke-free legislation in a vulnerable population group as pregnant women.