OBSTETRICS
Changes in Smoking During Pregnancy in Ontario, 1995 to 2010: Results From the Canadian Community Health Survey

https://doi.org/10.1016/S1701-2163(15)30436-9Get rights and content

Abstract

Objective

The objectives of this study were (1) to examine changes in smoking behaviour across time in pregnant women in Ontario (relative to non-pregnant women and men) and (2) to assess whether, among pregnant women, changes across time vary as a function of sociodemographic characteristics.

Methods

This study used data from the Canadian Community Health Survey. The study sample included 15- to 49-year-old residents of Ontario. Multivariable logistic regression, with interactions between time period and the characteristic of interest, was used to examine whether changes varied across time according to (1) group (pregnant women, non-pregnant women, men; two-year intervals, 2001 to 2010) and (2) pregnant subgroup (maternal age, maternal marital status, maternal education; 1995 to 2000 [n = 3745], 2001 to 2005 [n = 5084], and 2006 to 2010 [n = 2900]).

Results

A decrease in the prevalence of smoking across time was seen in all groups but was smaller in pregnant women than in non-pregnant women (23.5% vs. 30.8%). Among pregnant women, interactions between time period and maternal age, maternal marital status, and maternal education were statistically significant. The prevalence of smoking during pregnancy decreased in older, married, and more highly educated women, but increased in younger women (by 8.2%) and less educated women (by 12.8%). Although the prevalence of smoking during pregnancy decreased in unmarried women, the change was smaller than in married women.

Conclusion

Although the prevalence of smoking in pregnant women is decreasing over time, the decrease is smaller than that in non-pregnant women. Pregnant subgroups particularly resistant to change include younger, unmarried, and less educated mothers. These findings suggest there are subgroups that should be targeted more deliberately by public health interventions.

Résumé

Objectif

Cette étude avait pour objectif (1) d’examiner les modifications des comportements quant au tabagisme avec le temps chez les femmes enceintes de l’Ontario (par comparaison avec les femmes n’étant pas enceintes et les hommes) et (2) de chercher à déterminer si, chez les femmes enceintes, ces modifications avec le temps variaient en fonction de caractéristiques sociodémographiques.

Méthodes

Dans le cadre de cette étude, nous avons utilisé des données tirées de l’Enquête sur la santé dans les collectivités canadiennes. L’échantillon d’étude englobait les résidentes de l’Ontario dont l’âge se situait entre 15 et 49 ans. Une régression logistique multivariée (tenant compte des interactions entre la période et la caractéristique d’intérêt) a été utilisée pour chercher à déterminer si les modifications variaient avec le temps en fonction (1) du groupe (femmes enceintes, femmes n’étant pas enceintes, hommes; intervalles de deux ans, 2001-2010) et (2) du sous-groupe de grossesse (âge maternel, état matrimonial maternel, niveau de scolarité maternel; 1995-2000 [n = 3 745], 2001-2005 [n = 5 084] et 2006-2010 [n = 2 900]).

Résultats

Bien qu’une baisse de la prévalence du tabagisme avec le temps ait été constatée dans tous les groupes, cette baisse était plus faible chez les femmes enceintes que chez les femmes n’étant pas enceintes (23,5 % vs 30,8 %). Chez les femmes enceintes, les interactions entre la période et l’âge maternel, l’état matrimonial maternel et le niveau de scolarité maternel étaient significatives sur le plan statistique. La prévalence du tabagisme pendant la grossesse connaissait une baisse chez les femmes plus âgées, mariées et disposant d’un niveau de scolarité supérieur, tandis qu’il connaissait une hausse chez les jeunes femmes (de l’ordre de 8,2 %) et chez les femmes disposant d’un niveau de scolarité inférieur (de l’ordre de 12,8 %). Bien que la prévalence du tabagisme pendant la grossesse ait connu une baisse chez les femmes n’étant pas mariées, cette modification a été de plus faible envergure que chez les femmes mariées.

Conclusion

Bien que la prévalence du tabagisme chez les femmes enceintes connaisse une baisse avec le temps, cette baisse est de plus faible envergure que chez les femmes n’étant pas enceintes. Parmi les sous-groupes de femmes enceintes particulièrement résistantes au changement, on trouvait les femmes plus jeunes, non mariées et disposant d’un niveau de scolarité inférieur. Ces résultats semblent indiquer que certains sous-groupes devraient être ciblés de façon plus délibérée par les interventions de santé publique.

Section snippets

INTRODUCTION

Smoking is the leading cause of preventable morbidity and premature mortality worldwide.1 The risks of smoking are compounded during pregnancy because smoking negatively affects both maternal health and fetal health.2., 3., 4. In order to gauge the success of public health programs aimed at reducing the prevalence of smoking during pregnancy, information is needed on changes in smoking behaviour over time and, in particular, on subgroups of pregnant women who may need more targeted

METHODS

This was a secondary analysis of the Canadian Community Health Survey (CCHS). Each cycle of the CCHS was a cross-sectional survey that was representative of Canadians 12 years and older living in private dwellings. Access to the Research Data Centres Program was obtained through the Social Sciences and Humanities Research Council. For this study, data were obtained from Cycles 1.1 (2001 to 2002), 2.1 (2003 to 2004), 3.1 (2005 to 2006), and 4.1 (2007 to 2008) and from the 2009 and 2010 annual

RESULTS

Descriptive statistics for the sample of pregnant women across the three time periods of interest are included in the Table.

There were differential changes across time in smoking behaviour according to group membership (i.e., pregnant women, non-pregnant women, and men), as reflected in a statistically significant interaction between time period and group (P < 0.001) (Figure 1). Although smoking rates were lowest in pregnant women throughout the study period, the greatest decrease in smoking

DISCUSSION

The prevalence of smoking among pregnant women decreased between 2001–2002 and 2009–2010. This finding is consistent with the 2008 Canadian Perinatal Surveillance System report, which, also using CCHS data, showed a 24.7% decrease in the prevalence of smoking during pregnancy (2000–2001 to 2005).7 However, our study adds to the literature by showing that the decrease among pregnant women was smaller than that seen in non-pregnant women in the same time period. Changes in smoking behaviour in

CONCLUSION

We found that although the prevalence of smoking in pregnant women is decreasing over time, this decrease is smaller than that seen in non-pregnant women. Pregnant subgroups particularly resistant to change include younger, unmarried, and less educated mothers. Our findings suggest that these subgroups should be targeted more deliberately by public health interventions in order to meet the goals of the Ontario Tobacco Strategy.

REFERENCES (30)

  • A. Castles et al.

    Effects of smoking during pregnancy

    Am J Prev Med

    (1999)
  • G.J. Colman et al.

    Trends in smoking before, during, and after pregnancy in ten states

    Am J Prev Med

    (2003)
  • F. Zhang et al.

    Simulation-based power calculations for designing interrupted time series analyses of health policy interventions

    J Clin Epidemiol

    (2011)
  • A.D. Lopez

    The evolution of the Global Burden of Disease framework for disease, injury and risk factor quantification: developing the evidence base for national, regional, and global public health action

    Global Health

    (2005)
  • G.C. Windham et al.

    Evidence for an association between environmental tobacco smoke exposure and birthweight: a meta-analysis and new data

    Paediatr Perinat Epidemiol

    (1999)
  • S. Cnattingius

    The epidemiology of smoking during pregnancy: smoking prevalence, maternal characteristics, and pregnancy outcomes

    Nicotine Tob Res

    (2004)
  • Ontario Tobacco Research Unit

    Project evaluations: a coordinated review [special reports: monitoring the Ontario tobacco strategy, 2002/2002]

    (2002)
  • Eastern Ontario Health Unit

    Community health: Ontario tobacco strategy

    (2006)
  • Public Health Agency of Canada
  • Public Health Agency of Canada

    Perinatal health indicators for Canada 2013: a report from the Canadian Perinatal Surveillance System

    (2013)
  • M. Mohsin et al.

    Socio-demographic factors associated with smoking and smoking cessation among 426,344 pregnant women in New South Wales, Australia

    BMC Public Health

    (2005)
  • V.W. Jaddoe et al.

    Active and passive smoking during pregnancy and the risks of low birthweight and preterm birth: the Generation R Study

    Paediatr Perinatol Epidemiol

    (2008)
  • S.H. Ebrahim et al.

    Trends in pregnancy-related smoking rates in the United States, 1987–1996

    J Am Med Assoc

    (2000)
  • J.M. Paterson et al.

    Stopping smoking during pregnancy: are we on the right track?

    Can J Public Health

    (2003)
  • M. Mohsin et al.

    Socioeconomic correlates and trends in smoking in pregnancy in New South Wales

    Australia. J Epidemiol Community Health

    (2011)

    • Cited by (12)

    • Dysfunctional Uterine Activity in Labour and Premature Adverse Cardiac Events: Population-Based Cohort Study

      2018, Canadian Journal of Cardiology
      Citation Excerpt :

      Additionally, among women with a prolonged first stage of labour, the prevalence of common cardiometabolic risk factors within 24 months before index the delivery date was only 3.4% for obesity, 5.9% for diabetes mellitus, and 3.8% for chronic hypertension. The 2% rate of tobacco use observed herein is much less than the 10% rate reported among surveyed pregnant women in Ontario.21 Although the women in this study reflect Ontarian women who conceive and maintain a pregnancy, those who do not conceive might have a different cardiometabolic or health profile.

    • Smoking during pregnancy: changes and associated risk factors in Spain, 1980-2016

      2022, Journal of Public Health (United Kingdom)

    • Why are babies in Canada getting smaller?

      2022, Health Reports

    • Electronic cigarette use (vaping) and patterns of tobacco cigarette smoking in pregnancy- evidence from a population-based maternity survey in England

      2021, PLoS ONE

    • Factors related to Pregnancy Status Among Lebanese Women During COVID-19 Confinement

      2021, Research Square

    • Factors related to Pregnancy Outcome Among Lebanese Women During COVID-19 Confinement

      2020, Research Square
    View all citing articles on Scopus

    Competing Interests: None declared.

    View full text
    Copyright © 2014 Society of Obstetricians and Gynaecologists of Canada. Published by Elsevier Inc. All rights reserved.