[Determinant factors of smoking cessation during pregnancy]

Predictors of smoking cessation during pregnancy: a systematic review and meta-analysis

AIM

To identify factors found in the research literature to be associated with smoking cessation in pregnancy.

METHODS

Electronic searches of the bibliographic databases of PubMed, EMBASE, PsycINFO, Elsevier, Scopus and ISI Web of Science were conducted to April 2017. All studies reporting factors associated with smoking cessation or continuing smoking during pregnancy were included and reviewed systematically, irrespective of study design. The Newcastle-Ottawa Quality Assessment Scale was used to assess the study quality. The DerSimonian & Laird random-effects model was used to conduct meta-analyses, and where effect estimates were reported for factors included in at least three studies.

RESULTS

Fifty-four studies, including 505 584 women globally who smoked before pregnancy, 15 clinical trials and 40 observational studies, were included in the review and 36 (65.5%) were considered to be of high quality. This review identified 11 socio-demographic, seven socially related, 19 smoking behaviour-related, five pregnancy-related, six health-related and six psychological factors that were associated significantly with smoking cessation during pregnancy. The most frequently observed significant factors associated with cessation were: higher level of education, pooled odds ratio (OR), 95% confidence interval (CI) = 2.16 (1.80-2.84), higher socio-economic status: 1.97 (1.20-3.24), overseas maternal birth: 2.00 (1.40-2.84), Medicaid coverage or private insurance: 1.54 (1.29-1.85), living with partner or married: 1.49 (1.38-1.61), partner/other members of the household do not smoke: 0.42 (0.35-0.50), lower heaviness of smoking index score: 0.45 (0.27-0.77, lower baseline cotinine level: 0.78 (0.64-0.94), low exposure to second-hand smoking: 0.45 (0.20-1.02), not consuming alcohol before and/or during pregnancy: 2.03 (1.47-2.80), primiparity: 1.85 (1.68-2.05), planned breastfeeding:1.99 (1.94-2.05), perceived adequate pre-natal care: 1.74 (1.38-2.19), no depression: 2.65 (1.62-4.30) and low stress during pregnancy: 0.58 (0.44-0.77).

CONCLUSION

A wide range of socio-demographics, relationship, social, smoking-related, pregnancy-related, health and psychological factors have been found to predict smoking cessation in pregnancy.

The Smoking MUMS (Maternal Use of Medications and Safety) Study: protocol for a population-based cohort study using linked administrative data

INTRODUCTION

Approximately 14% of Australian women smoke during pregnancy. Although the risk of adverse outcomes is reduced by smoking cessation, less than 35% of Australian women quit smoking spontaneously during pregnancy. Evidence for the efficacy of bupropion, varenicline or nicotine replacement therapy as smoking cessation aids in the non-pregnant population suggest that pharmacotherapy for smoking cessation is worth exploring in women of childbearing age. Currently, little is known about the utilisation, effectiveness and safety of pharmacotherapies for smoking cessation during pregnancy; neither the extent to which they are used prior to pregnancy nor whether their use has changed in response to related policy reforms. The Smoking MUMS (Maternal Use of Medications and Safety) Study will explore these issues using linked person-level data for a population-based cohort of Australian mothers.

METHODS AND ANALYSIS

The cohort will be assembled by linking administrative health records for all women who gave birth in New South Wales or Western Australia since 2003 and their children, including records relating to childbirth, use of pharmaceuticals, hospital admissions, emergency department presentations and deaths. These longitudinal linked data will be used to identify utilisation of smoking cessation pharmacotherapies during and between pregnancies and to explore the associated smoking cessation rates and maternal and child health outcomes. Subgroup and temporal analyses will identify potential differences between population groups including indigenous mothers and social security recipients and track changes associated with policy reforms that have made alternative smoking cessation pharmacotherapies available.

ETHICS AND DISSEMINATION

Ethical approval has been obtained for this study. To enhance the translation of the project's findings into policy and practice, policy and clinical stakeholders will be engaged through a reference group and a policy forum will be held. Outputs from the project will include scientific papers and summary reports designed for policy audiences.

Prevalence of smoking during pregnancy and associated risk factors among Canadian women: a national survey

Background

Cigarette smoking carries a threat both to the expecting mother and her newborn. Data on the prevalence and predictors of smoking during pregnancy is limited in Canada. Canadian studies are mainly representative of specific cities and/or provinces. Therefore, the study aims to assess the prevalence of smoking during pregnancy and its associated risk factors throughout the Canadian provinces and territories.

Methods

The analysis was based on the Maternity Experience Survey targeting women aged ≥15 years who had singleton live births during 2005/06 in the Canadian provinces and territories. The outcome was ever smoking during the thirst trimester of pregnancy. Socio-economic factors, demographic factors, maternal characteristics, and pregnancy related factors that proved to be significant at the bivariate level were considered for a logistic regression analysis. Bootstrapping was performed to account for the complex sampling design.

Results

The sample size was 6,421 weighted to represent 76,508 Canadian women. The prevalence of smoking during pregnancy was 10.5%, whereby smoking mothers consumed on average 7 cigarettes a day (95% Confidence interval - CI: 6.5-7.4; SD = 5.7). Regression analysis revealed that mothers who smoked during pregnancy were more likely to be of low socio-economic status, non-immigrant, single and passive smokers during pregnancy. Not attending prenatal classes and experiencing stressful events before/during pregnancy also increased the mothers' odds of smoking during pregnancy. While the age of the mother's first pregnancy was negatively associated with smoking during pregnancy, the mother's current age was positively associated with it.

Conclusion

Smoking during pregnancy is still prevalent among Canadian women. The findings may be useful to enhance smoking prevention programs and integrated health promotion strategies to promote positive health behaviors among disadvantaged pregnancies.

[Efficiency and risk factors in the cognitive-behavioural treatment for smoking cessation in pregnancy]

BACKGROUND AND OBJECTIVE

The aim of this study is to quantify the efficiency of the cognitive-behavioural treatment for smoking cessation in pregnancy and to evaluate the risk factors of success or failure for the abstinence before the childbirth.

PATIENTS AND METHOD

We studied 74 pregnant smoking women who, between January 2003 and January 2004, came to their obstetric regular control in the Hospital Casa Maternitat-Hospital Clínic i Provincial de Barcelona, and who voluntarily acceded to the cognitive-behavioural treatment without replacement of nicotine for the smoking cessation that they were offered.

RESULTS

44% of women who made the program of visits came abstinent to the childbirth, and of them, 93.1% was abstinent during the quarantine. 51.5% reduced the consumption and 4.5% didn't change or increased the consumption. The fact that someone smokes at home (p = 0.006), the degree of dependence to the nicotine (p = 0.015) and a consumption of coffee superior to 3 daily cups (p = 0.039), in an equation of logistic regression, classified both groups (abstinence/not abstinence).

CONCLUSIONS

The efficiency of a program based on cognitive-behavioural therapy, without replacement of nicotine, for the smoking cessation in the pregnancy is confirmed in our sample. We propose to consider risk factors of treatment failure the fact that someone smokes at home and a daily high consumption of coffee.

Smoking among pregnant women in Cantabria (Spain): trend and determinants of smoking cessation

Background

Cantabria (Spain) has one of the highest prevalence of smoking among women of the European Union. The objectives are to assess the trend of smoking during pregnancy in a five-year period and the determinants of smoking cessation during pregnancy in Cantabria.

Methods

A 1/6 random sample of all women delivering at the reference hospital of the region for the period 1998–2002 was drawn, 1559 women. Information was obtained from personal interview, clinical chart, and prenatal care records. In the analysis relative risks and 95% confidence intervals were estimated. Multivariable analysis was carried out using stepwise logistic regression.

Results

Smoking prior to pregnancy decreased from 53.6% in 1998 to 39.4% in 2002. A decrease in smoking cessation among women smoking at the beginning of pregnancy was observed, from 37.3% in 1998 to 20.6% in 2002. The mean number of cigarettes/day (cig/d) before pregnancy remained constant, around 16 cig/d, whereas a slight trend to increase over time was seen, from 7.7 to 8.9 cig/d. In univariate analysis two variables favoured significantly smoking cessation, although they were not included in the stepwise logistic regression analysis, a higher education level and to be married. The logistic regression model included five significant predictors (also significant in univariate analysis): intensity of smoking, number of previous pregnancies, partner's smoking status, calendar year of study period (these four variables favoured smoking continuation), and adequate prenatal care (which increased smoking cessation).

Conclusion

The frequency of smoking among pregnant women is very high in Cantabria. As smoking cessation rate has decreased over time, a change in prenatal care programme on smoking counseling is needed. Several determinants of smoking cessation, such as smoking before pregnancy and partner's smoking, should be also addressed by community programmes.

[Socioeconomic inequalities in the provision and uptake of prenatal care]

OBJECTIVE

To describe socioeconomic inequalities in the provision and uptake of prenatal care among women in Barcelona (Spain) between 1994 and 2003.

METHODS

Cross-sectional study of women in Barcelona who delivered a child without birth defects. Information was obtained from hospital medical records and a personal interview with women included in the Barcelona Birth Defects Registry, containing a random sample of 2% of all pregnant women in the city (n = 2299).

DEPENDENT VARIABLES

number of obstetric visits, the trimester of the first visit, the number of obstetric ultrasound scans, the fifth-month diagnostic ultrasound scan, invasive procedures, prenatal folic acid intake, pregnancy planning, smoking and smoking cessation. The independent variables were maternal age and social class. Logistic regression models were filted for each dependent variable.

RESULTS

In social classes with manual occupations, there was a higher proportion of pregnant women who attended less than six obstetric visits and who attended the first obstetric visit after the first trimester. Moreover, these women were less likely to have undergone an invasive procedure, to have taken folic acid supplements, to have planned the pregnancy, to be non-smokers and to stop smoking. In the more privileged classes, there was a higher proportion of women who attended more than 12 obstetric visits and who underwent more than three ultrasound scans.

CONCLUSIONS

Socioeconomic inequalities were found in the provision and uptake of prenatal care in Barcelona. Uptake was greater in the more advantaged social classes but excessive medicalization was found in all classes. Rationalizing the use of healthcare resources and reducing excessive medicalization would reduce inequalities in prenatal care in Barcelona.

Consumo de tabaco durante el embarazo en España: análisis por años, comunidades autónomas y características maternas

BACKGROUND AND OBJECTIVE

The information about the convenience of non-smoking during pregnancy has increased in recent years. For this reason, we studied weather there has been any variation in smoking habits by pregnant women in Spain.

SUBJECTS AND METHOD

We used data from 31,056 mothers of infants without congenital defects, from all the Spanish Autonomic Regions. These data had been collected with the same methodology all over the country. The evolution of maternal smoking habit was analyzed by years, Autonomic Regions and maternal characteristics.

RESULTS

During the last years of the study (1995-2002), 30.31% of mothers smoked during pregnancy, with variations among different ethnic groups. It was observed a secular increase in the prevalence of smoker mothers from 1978 to 1991, which was further stable in about 27-28%. There was no secular decrease in the analyses by maternal age, number of cigarettes, and Autonomic Regions. Only smoker mothers with higher educational levels diminished smoking in 1993, with it being stable in about 23%. Mothers younger than 25 years were the heaviest smokers in all the years of the study. We confirmed a close relationship between tobacco, alcohol and illegal drugs consumption.

CONCLUSIONS

Our data indicate that the prevalence of women smoking during pregnancy has not diminished over the years or by Autonomic Regions, although 19.19% of smoker pregnant women quit smoking during the first months of pregnancy. Moreover, the heaviest smoker mothers were the youngest ones in all the years of the study. These results show the need to increase the information for women so that they quit smoking before pregnancy.

[Evolution of tobacco habits during pregnancy and postpartum period]

OBJECTIVE

To describe how smoking evolved during pregnancy and a long postpartum period, with analysis of the factors associated with giving up tobacco.

DESIGN

Retrospective, descriptive study.

SETTING

Badia del Vallès Primary Care Centre (Barcelona).

PARTICIPANTS

Women with pregnancies coming to term over a 3-year period (n=309, 68% of the target population).

MAIN MEASUREMENTS

Tobacco dependency before pregnancy. Giving up during pregnancy and related factors (social and personal, nature of tobacco habit, health beliefs). Backsliding after birth.

RESULTS

50% smoked before pregnancy. 46% of these gave up smoking during pregnancy and 44% cut down. In primigravidae, there was greater risk of their continuing to smoke, the greater their previous tobacco consumption was (OR=5.3 if > or =20 cigarettes a day and OR=4.7 for 10-19 cigarettes a day) or if they did not believe in the effect of tobacco on the baby's health (OR=3.9). In women pregnant for the second time or more, it was associated with not giving up tobacco in previous pregnancies (OR=43.8) and with their partner's tobacco habit (OR=7.2). In the 2 years after birth 80% of those who gave up relapsed.

CONCLUSIONS

In our milieu a high prevalence of smokers before pregnancy coexists with a high rate of giving up during pregnancy. In all, 1 in every 4 women smokes during pregnancy. Giving up tobacco was related to factors such as dependency, motivation, environment and prior experience.

Smoking cessation and associated factors during pregnancy

OBJECTIVE

To examine smoking habits before and during pregnancy, as well as factors associated with smoking cessation, in three European settings.

METHODS

Women seeking antenatal care in Ashford (UK), Minorca and Barcelona (Spain) were recruited to the Asthma Multicenter Infant Cohort Study (AMICS). Questionnaires inquiring into the smoking habits of each woman and her partner, demographic data, occupation, educational level, number of previous children, breast feeding, alcohol intake, and history of asthma and of other allergic diseases were completed during pregnancy and in the first year after delivery.

RESULTS

A total of 1,572 pregnant women were included in the three cohorts. Smoking prior to pregnancy was more common in Barcelona (46.2%) than in Minorca (39.8%) or Ashford (31.6%). Cessation rates during pregnancy also differed: 18% of women in Ashford, 20.4% in Minorca and 31.9% in Barcelona were still smoking during the first trimester. In a multivariate regression model, the factors showing a significant (negative) association with smoking cessation during pregnancy were having older children, having a partner who smoked and starting smoking at a young age.

CONCLUSIONS

Baseline smoking habits and changes in smoking habits during pregnancy significantly differed between the three communities studied. Women pregnant with their first child, those who had started smoking at a later age and those whose partners were non-smokers were more likely to stop smoking when pregnant.

[Effectiveness of two health interventions to get pregnant women to give up smoking]

OBJECTIVE

To evaluate the effectiveness of the group intervention for getting pregnant women to give up tobacco consumption, measured by means of carbon monoxide levels in air breathed out, compared with a minimum intervention.

DESIGN

Randomised clinical trial.

SETTING

Four primary care teams from Area 9 of IMSALUD-Madrid.

PARTICIPANTS

All the pregnant women attending for consultation with the midwives of the four PC teams involved during the study period, who are smoking at least one cigarette a day when they find out they are pregnant and who want to take part in the study once they have been informed of it. Intervention. The subjects included will be randomised into 2 intervention groups. The minimum intervention will consist of brief personal counselling (3 to 5 minutes) on why they should give up smoking, especially now they are pregnant. The group intervention will involve 3 sessions lasting approximately an hour and a half.

[Individually tailored medical counseling for pregnant smokers]

OBJECTIVES

To identify the characteristics of smoking addiction in a group of pregnant women, to evaluate the efficacy of medical counseling tailored to the patient's stage in the cessation process and to examine factors that might affect the ability of a woman to quit smoking during pregnancy.

PATIENTS AND METHODS

One hundred sixteen women (mean age 29.71 5.44 years; range 15-41) were referred by obstetricians to a respiratory medicine specialist if they continued smoking after being advised to quit. The information each woman received was appropriate to her stage in the cessation process and covered the risks that smoking posed for her child and the benefits that would come from quitting. Each woman was provided with guidelines for quitting and helped to choose the first day to start the cessation process. The women received follow-up counseling sessions after the first and third months.

RESULTS

Twenty-seven women (23.3%) quit smoking, 18 (15.52%) advanced a stage in the cessation process and 30 (25.86%) smoked less. Overall, the program benefited 60 women (51.7%) who quit smoking, reduced the number of cigarettes they smoked or progressed to a new stage.

CONCLUSIONS

The results reveal that most pregnant smokers need the intervention of specialists with knowledge of smoking addiction to facilitate the cessation process.

[Impact of medical counselling on giving up smoking during pregnancy]

OBJECTIVE

Women s tobacco consumption has increased in Spain in recent years, especially among women of reproductive age. This study aims to evaluate the impact of medical counselling integrated into pre-natal care on tobacco consumption during pregnancy and the period after delivery.

DESIGN

Quasi-experimental intervention study.Setting. Hospital del Mar, Barcelona.

PATIENTS

219 patients who attended the Hospital del Mar for delivery during 1996 (control group) and 169 patients seen during their pregnancies at the same hospital in 1997 (intervention group).

INTERVENTIONS

The control group patients had received normal care. The pregnant women in the intervention group received systematic structured counselling on giving up smoking, backed up by a special brochure composed for this purpose.

MEASUREMENTS AND RESULTS

The intervention and control groups showed no statistically significant differences either in their social or demographic variables or in their tobacco consumption. In both groups the evolution of their smoking during pregnancy was determined during their pre-natal visits and six months after delivery through a telephone interview. 44 of the women in the control group (20.1%) gave up smoking before their first pre-natal visit, and 11 (5%) gave up during pregnancy. In the intervention group 26 (17.7%) had given up spontaneously and 16 (10.9%) gave up during pregnancy. Of those who gave up completely during pregnancy, 36.4% of women in the control group and 64.3% in the intervention group remained abstinent at six months (P=.002).

CONCLUSIONS

Counselling at pre-natal check-ups to give up smoking lightly increases the number of women who give up and reduces significantly the number of post-delivery backsliders.

[Neonatal effects of smoking habit during pregnancy and sociodemographic determinants in Barcelona, Spain]

BACKGROUND

Smoking during pregnancy poses a health risk for the fetus which may later extend to the child and adult, with higher probability of respiratory problems. The aim of this study was the to investigate the correlation between smoking during pregnancy and the neonatal characteristics and sociodemographic determinants of smoking habit during pregnancy.

PATIENTS AND METHODS

Study subjects were 419 mothers and their newborns in Barcelona, Spain. Data on smoking habits were collected using a structured questionnaire. We measured cotinine in umbilical cord blood as a biomarker of exposition to tobacco smoke. Concentrations of cotinine were determined using a radioimmunoassay.

RESULTS

29% interviewed mothers declared daily cigarette consumption during the third trimester of pregnancy, while the biomarker test showed that 34% mothers were smoking at the end of pregnancy. Smoking habit during pregnancy, assessed by means of either the questionnaire or the biomarker, correlated negatively with anthropometric parameters (weight, length and head circumference) of the newborn. The smoking habit was not associated with social class and age, although it was lower in primigravid mothers.

CONCLUSIONS

Unlike other European countries, there is a widespread smoking consumption during pregnancy in Spain, regardless of the social class and maternal age. Reduction of both active smoking and exposition to environmental tobacco smoke represent key elements in the prevention of newborns' morbidity and mortality.