Smoking in pregnancy: a way to cope with excessive workload?

Exposure to psychosocial work strain and changes in smoking behavior during pregnancy - a longitudinal study within the Danish National Birth Cohort

Objective:

Knowledge of the relationship between psychosocial strain in the work environment and smoking during pregnancy is scarce. This study aimed to examine the association between psychosocial job strain and change in smoking behavior during pregnancy.

Methods:

The cohort included 65 645 pregnancies from the Danish National Birth Cohort (1996–2002), where pregnant women were interviewed on job factors and lifestyle during the first and third trimesters. Smoking was categorized into non-, non-daily, and daily smoking at each interview. Psychosocial job strain was categorized into four groups based on the concept of Karasek’s demand–control model: low strain (reference), passive, active and high strain. Associations between psychosocial strain and change in smoking status between the first and second interviews were analyzed by multinomial logistic regression, separately for each smoking category at first interview.

Results:

Non-smoking women exposed to high strain work were more likely to become daily smokers [adjusted odds ratio (OR_adj) 1.41, (95% confidence interval (CI) 1.08–1.83)] compared to non-smoking women exposed to low strain work. Non-smoking women exposed to passive work were more likely to become both non-daily and daily smokers [OR_adj 1.59 (95% CI 1.21–2.08) and OR_adj 1.32 (95% CI 1.03–1.70), respectively]. Daily smoking women exposed to high strain work were less likely to decrease their smoking [OR_adj 0.57 (95% CI 0.32–0.99)] compared to daily smoking women exposed to low strain work.

Conclusions:

Psychosocial strain influenced the women’s smoking behavior during pregnancy, especially in job types with low control.

Psychosocial problems and continued smoking during pregnancy

The present study examined the association of several psychosocial problems with continued smoking during pregnancy. Based on a population-based cohort study among pregnant women in Amsterdam (n=8266), women who smoked before pregnancy were included in this study (n=1947). Women completed a questionnaire around the 12th week of gestation. Based on whether they smoked in the past week, participants were categorized as quitters or non-quitters. Depressive symptoms (CES-D), anxiety (STAI), pregnancy-related anxiety, job strain, parenting stress and physical/sexual violence were measured. Multiple logistic regression analyses were performed. After adjustment for sociodemographic and smoking-related covariates, low and high levels of pregnancy-related anxiety, exposure to physical/sexual violence, and high job strain were significantly associated with continued smoking during pregnancy. Intensive and comprehensive smoking cessation programs are required for pregnant women, which includes the management of psychosocial problems.

The influence of in-pregnancy smoking cessation programmes on partner quitting and women's social support mobilization: a randomized controlled trial [ISRCTN89131885]

BACKGROUND

Smoking cessation interventions in pregnancy could influence a woman's social behaviour and her partner's smoking behaviour, but this has not been examined in any published randomized trials.

METHOD

918 women smoking at booking for antenatal care were enrolled in a cluster-randomized trial of three interventions: standard care, self-help manual and enhanced stage-based counselling, or self-help manual, enhanced stage-based counselling and use of an interactive computer program. The outcomes were change in social support received by women between booking for maternity care and 30 weeks gestation and 10 days postpartum and reported cessation in the woman's partner at these times.

RESULTS

Few pregnant women's partners stopped smoking (4.1% at 30 weeks of gestation and 5.8% at 10 days postpartum) and the probability of quitting did not differ significantly by trial arm. Women's scores on the Inventory of Socially Supportive Behaviors showed a slight decline from booking to 30 weeks gestation, and a slight increase to 10 days postpartum, but these changes did not differ significantly by trial arm.

CONCLUSION

The stage-based interventions tested in this trial aimed partly to influence women's mobilization of support and might have influenced partners' quitting, but there was no evidence that they did so. Given that women and their partners often stopped smoking together, future interventions to prevent smoking in pregnant women could encourage both partners to quit together.

The association between smoking during pregnancy and hospital inpatient costs in childhood

Although the health sequelae of smoking during pregnancy are well documented, relatively little is known about its long-term economic implications. The objective of this study was to analyse individual-level data on maternal smoking behaviour and sociodemographic, perinatal and resource utilisation variables in order to estimate the association between smoking during pregnancy and hospital inpatient service utilisation and costs through the first 5 years of the infant's life. Data from the Oxford Record Linkage Study, a collection of birth registrations, death certificates and statistical abstracts of hospital inpatient and day case admissions formed the basis of the investigation. The study population comprised all infants born to women who both lived and delivered in Oxfordshire or West Berkshire during the period 1 January 1980-31 December 1989 (n = 119,028). The cost of each hospital admission, including the initial birth admission, was estimated by multiplying the length of stay by the per diem cost of the respective specialty (pound 1998-1999 sterling). The effect of maternal smoking behaviour on cumulative 5-year hospital inpatient service utilisation and costs was analysed in a series of multivariate analyses, taking account of confounding clinical and sociodemographic factors. Infants born to women who reported smoking during pregnancy were hospitalised for a significantly greater number of days than infants born to women who had either never smoked or had smoked in the past (P < 0.0001). Over the first 5 years of life, the adjusted mean cost difference was estimated at pound sterling 462 (95%CI: pound sterling 353-pound sterling 571) when infants born to women who smoked at least 20 cigarettes per day were compared to infants of non-smoking mothers, and pound sterling 307 (95%CI: pound sterling 221-pound sterling 394) when infants born to women who smoked 10-19 cigarettes per day were compared to infants of non-smoking mothers (P < 0.0001). The results of this study should add an economic dimension to the importance of providing smoking cessation services for pregnant women.

Interventions for promoting smoking cessation during pregnancy

BACKGROUND

Smoking remains one of the few potentially preventable factors associated with low birthweight, preterm birth and perinatal death.

OBJECTIVES

To assess the effects of smoking cessation programs implemented during pregnancy on the health of the fetus, infant, mother, and family.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Tobacco Addiction Group trials register (July 2003), MEDLINE (January 2002 to July 2003), EMBASE (January 2002 to July 2003), PsychLIT (January 2002 to July 2003), CINAHL (January 2002 to July 2003), and AUSTHEALTH (January 2002 to 2003). We contacted trial authors to locate additional unpublished data. We handsearched references of identified trials and recent obstetric journals.

SELECTION CRITERIA

Randomised and quasi-randomised trials of smoking cessation programs implemented during pregnancy.

DATA COLLECTION AND ANALYSIS

Four reviewers assessed trial quality and extracted data independently.

MAIN RESULTS

This review included 64 trials. Fifty-one randomised controlled trials (20,931 women) and six cluster-randomised trials (over 7500 women) provided data on smoking cessation and/or perinatal outcomes. Despite substantial variation in the intensity of the intervention and the extent of reminders and reinforcement through pregnancy, there was an increase in the median intensity of both 'usual care' and interventions over time. There was a significant reduction in smoking in the intervention groups of the 48 trials included: (relative risk (RR) 0.94, 95% confidence interval (CI) 0.93 to 0.95), an absolute difference of six in 100 women continuing to smoke. The 36 trials with validated smoking cessation had a similar reduction (RR 0.94, 95% CI 0.92 to 0.95). Smoking cessation interventions reduced low birthweight (RR 0.81, 95% CI 0.70 to 0.94) and preterm birth (RR 0.84, 95% CI 0.72 to 0.98), and there was a 33 g (95% CI 11 g to 55 g) increase in mean birthweight. There were no statistically significant differences in very low birthweight, stillbirths, perinatal or neonatal mortality but these analyses had very limited power. One intervention strategy, rewards plus social support (two trials), resulted in a significantly greater smoking reduction than other strategies (RR 0.77, 95% CI 0.72 to 0.82). Five trials of smoking relapse prevention (over 800 women) showed no statistically significant reduction in relapse.

REVIEWERS' CONCLUSIONS

Smoking cessation programs in pregnancy reduce the proportion of women who continue to smoke, and reduce low birthweight and preterm birth. The pooled trials have inadequate power to detect reductions in perinatal mortality or very low birthweight.

The working-class context of pregnancy smoking

The risk of smoking during pregnancy in the US is strongly associated with women's individual socioeconomic status (SES) but little is known about the influence of local area context. The aim of this study was to examine whether local-area characteristics increase the risk of smoking during pregnancy above and beyond individual SES. In a hospital-based cohort of 878 pregnant women in California, who delivered between 1980 and 1990, we compared risk of smoking during pregnancy based on individual and local-area factors. Adjusting for individual SES, neighborhood social class was related to smoking in early pregnancy. Living in a predominantly working-class area significantly increased the risk of pregnancy smoking for both working-class and non-working-class women. However, local-area economic and demographic indicators were not related to smoking early in pregnancy. Individual and family characteristics alone may be insufficient to explain smoking during pregnancy; the social class context of the places in which pregnant women live may also influence this behavior.

How to prevent exposure to tobacco smoke among small children: a literature review

There are many reviews of current knowledge about smoking cessation in general within the health service, which also contain guidelines about smoking cessation during pregnancy. Our aim was to review methods in child healthcare for preventing the exposure of children to tobacco smoke. Since passive smoking starts during pregnancy, we also considered methods in antenatal care. We did a search for relevant articles, especially on randomized, controlled trials, in various databases, chiefly Medline. We mainly analysed studies from the last 10 y, concentrating on the actual interventions. In antenatal care the greatest effect comes from interventions based on behavioural strategies. These can lead to a doubling of the number of women who stop smoking during pregnancy. Purely factual information, on the other hand, has no great effect. The studies in child healthcare analysed here show that decisive factors for children not being exposed to passive smoking are a concentration on strengthening the parents' faith in their ability to create a smoke-free environment, and on behavioural strategies to achieve this goal, but not primarily on getting the parents to stop smoking. However, we need further studies of different types of interventions, geared to smokers with small children, before more specific recommendations can be given as to how child healthcare should design its tobacco-preventive work.

From in utero and childhood exposure to parental smoking to childhood cancer: a possible link and the need for action

The objective of the present work is to critically summarize published studies and reassess the state of knowledge on a highly controversial topic: the potential association between prenatal exposure to passive smoking as well as maternal active smoking and postnatal exposure to environmental tobacco smoke (ETS) and enhanced incidence of childhood cancer. Elements to be considered include the substantial proportion of pregnant women who remain smokers, the widespread nature of exposure to ETS during pregnancy as well as during childhood, the known toxicology of tobacco smoke, and in particular sidestream smoke, characterized by a rich carcinogen content, the specific metabolism of foetuses and new-borns and finally the amount of epidemiologic data already available. We conducted a thorough review of the literature to identify studies either exclusively dealing with the effects of passive smoking on the occurrence of childhood cancers or more generally etiologic studies of cancer, be it overall or site-specific. We identified close to 50 publications presenting pertinent results from epidemiological investigations and about 50 more on mechanisms and metabolism, smoking in pregnancy and exposure to ETS as well as selected reviews and commentaries. Collaborative epidemiological studies were conducted in the United Kingdom (UK), USA, Sweden, Netherlands and internationally (France, Italy). In addition, other studies were also available from the USA, UK, Canada, Australia, Sweden, Italy, Denmark and People's Republic of China. The vast majority were case-control studies dealing with all cancers, leukaemia and lymphomas, central nervous system (CNS) tumours, Wilms' tumour, retinoblastoma, neuroblastoma, hepatoblastoma, rhabdomyosarcoma, bone and soft tissues tumours, germ cell tumours, as well as specific histological types of leukaemias, lymphomas or CNS tumours. No strong association between maternal smoking in pregnancy and/or exposure to ETS and childhood cancer is found. Yet, several studies found slightly increased relative risks, generally smaller than 1.5, i.e. the order of magnitude associated with some recognized hazards of exposure to ETS (1.2 to 1.3 for adult lung cancer and cardiovascular diseases). Tumours most often found associated with maternal smoking in pregnancy or ETS exposure are childhood brain tumours and leukaemia-lymphoma, with risks up to two or greater in selected studies. In a few studies, risks associated with paternal smoking are higher than the maternal ones. This evidence from human studies coupled with demonstration of genotoxic effects on the foetus of exposure to metabolites of tobacco smoke, and demonstrable presence of adducts should lead to strong recommendations aiming at fully protecting foetuses, new-borns and infants from tobacco smoke.