Cigarette Smoking During Pregnancy: Do Complete Abstinence and Low Level Cigarette Smoking Have Similar Impact on Birth Weight?

Do smoking abstinence periods among pregnant smokers improve birth weight? A secondary analysis of a randomised, controlled trial

OBJECTIVES

Maternal smoking during pregnancy is associated with low birth weight (LBW). Reduction of cigarette consumption does not seem to improve birth weight but it is not known whether implementation of periods of smoking abstinence improves it. We assessed whether the number of 7-day periods of smoking abstinence during pregnancy may help reduce the number of newborns with LBW.

DESIGN AND SETTING

Secondary analysis of a randomised, controlled, multicentre, smoking cessation trial among pregnant smokers.

PARTICIPANTS

Pregnant women were included at <18 weeks of gestational age and assessed at face-to-face, monthly visits. Data of 407 singleton live births were analysed.

PRIMARY OUTCOME MEASURE

Newborns with low birth weight.

RESULTS

40 and 367 newborns were born with and without LBW, respectively. Adjusted for all available confounders, 3 or more periods of at least 7 days' smoking abstinence during pregnancy was associated with reduced likelihood of LBW compared with no abstinence periods (OR = 0.124, 95% CI 0.03 to 0.53, p = 0.005). Reduction of smoking intensity by at least 50% was not associated with birth weight.

CONCLUSION

Aiming for several periods of smoking abstinence among pregnant smokers unable to remain continuously abstinent from smoking may be a better strategy to improve birth weight than reducing cigarette consumption.

TRIAL REGISTRATION NUMBER

ClinicalTrials.gov NCT02606227.

Racial/Ethnic Disparities Impact the Real-World Effectiveness of a Multicomponent Maternal Smoking Cessation Program: Findings from the CTTP Cohort

INTRODUCTION

Smoking during pregnancy adversely affects perinatal outcomes for both women and infants. We conducted a retrospective cohort study of the state-funded Comprehensive Tobacco Treatment Program (CTTP) - the largest maternal tobacco cessation program in San Bernardino County, California - to determine the real-world program effectiveness and to identify variables that can potentially improve effectiveness.

METHODS

During 2012-2019, women who smoked during pregnancy were enrolled in CTTP's multicomponent behavioral smoking cessation program that implemented components of known efficacy (i.e., incentives, biomarker testing, feedback, and motivational interviewing).

RESULTS

We found that 40.1% achieved prolonged abstinence by achieving weekly, cotinine-verified, 7-day abstinence during 6 to 8 weeks of enrollment. Using intention-to-treat analyses, we computed that the self-reported point prevalence abstinence rate (PPA) at the six-month telephone follow-up was 36.7%. Cohort members achieving prolonged abstinence during the CTTP were five times more likely to achieve PPA six months after CTTP. Several non-Hispanic ethnicities (Black, Native American, White, or More than one ethnicity) in the cohort were two-fold less likely (relative to Hispanics) to achieve prolonged abstinence during CTTP or PPA at six months after CTTP. This disparity was further investigated in mediation analysis. Variables such as quitting during the first trimester and smoking fewer cigarettes at enrollment were also associated with achieving PPA at six months.

DISCUSSION

Racial/ethnic health disparities that have long been linked to a higher rate of maternal smoking persist even when the pregnant smoker enrolls in a smoking cessation program.

[Pregnant women's use of tobacco and electronic cigarettes: A cross sectional survey]

OBJECTIVES

The article aims to describe tobacco and e-cigarette use among pregnant women: estimate the prevalence, identify the determinants and motivations of these behaviours.

METHODS

Cross-sectional, multicentre, descriptive observational study using self-administered questionnaires for pregnant women who visited ELENA healthcare centers in May 2021.

RESULTS

Of 223 patients, 38% were smokers before pregnancy and 16% continued to smoke during pregnancy. Nearly all the smokers (98%) declared that they had reduced or stopped their tobacco use, mostly without help. Young age, lack of professional activity, an unfavourable reaction to the announcement of the pregnancy, heavy smoking before the pregnancy and the presence of a smoker spouse were associated with smoking during pregnancy. Our study identified 10% of vapers before pregnancy and 7.2% during pregnancy. Of those who vaped during pregnancy, 81% were smokers before pregnancy. Most of them used a nicotine containing liquid and 38% of vapers combined smoking and e-cigarettes during pregnancy. There was no association between vaping during pregnancy and smoking cessation. A minority of women had received information about smoking during pregnancy.

CONCLUSIONS

The use of electronic cigarettes by pregnant women is a poorly-known reality in France, yet it concerns approximately 7% of the women in our sample. Prospective studies on larger numbers are needed to assess the prevalence of vaping among French pregnant women and its evolution during pregnancy.

Active or passive maternal smoking increases the risk of low birth weight or preterm delivery: Benefits of cessation and tobacco control policies

In France, maternal smoking, active or passive, remains one of the highest in Europe. At the same time, there is an increase in the number of low birth weight (<2500 g) and premature (<37 weeks of amenorrhea) newborns. The objective of this narrative review is to examine the impact of active or passive maternal smoking on birth weight or prematurity rates, and to consider the benefits of policies to stop or control smoking. This is a narrative review that analyzes and discusses the major articles published over the past 20 years regarding the role of active or passive maternal smoking on the risk of low birth weight or preterm delivery. Articles were selected using the following keywords: maternal smoking, low birth weight, preterm birth, smoking cessation, passive smoking, exhaled carbon monoxide, tobacco control policies. Active smoking is associated, in a dose-response relationship, with increased risks of low birth weight and preterm delivery. Passive smoking, mainly related to the presence of a smoking spouse, increases the risk of low birth weight and preterm birth. Our review confirmed also the benefits of smoking cessation, even in the third trimester, in reducing the risk of small for gestation age or fetal growth restriction and preterm birth. Several studies of tobacco control policies have been shown to be effective in significantly reducing maternal smoking. There is sufficient evidence to infer a causal link between active or passive maternal smoking and low birth weight or preterm delivery. This causal link is compelling and sufficient to justify intensifying efforts to promote rapid progress in tobacco control policies, with the vision of a tobacco-free generation, and smoking cessation with best practices during preconception or pregnancy.

Effect of digital health, biomarker feedback and nurse or midwife-led counselling interventions to assist pregnant smokers quit: a systematic review and meta-analysis

OBJECTIVE

To assess the effect of digital health (DH), biomarker feedback (BF) and nurse or midwife-led counselling (NoMC) interventions on abstinence in pregnant smokers during pregnancy and postpartum.

SETTINGS

Any healthcare setting servicing pregnant women, including any country globally.

PARTICIPANTS

Pregnant women of any social, ethnic or geographical background who smoke.

METHODS

We searched Embase, Medline, Web Of Science, Google Scholar, PsychINFO, CINAHL and PubMed between 2007 and November 2021. We included published original intervention studies in English with comparators (usual care or placebo). Two independent assessors screened and abstracted data. We performed a random-effects meta-analysis, assessed risk of bias with the Cochrane Tool and used Grading of Recommendations Assessment, Development and Evaluation to assess the quality of evidence.

RESULTS

We identified 57 studies and included 54 in the meta-analysis. Sixteen studies assessed DH (n=3961), 6 BF (n=1643), 32 NoMC (n=60 251), 1 assessed NoMC with BF (n=1120) and 2 NoMC with DH interventions (n=2107). DH interventions had moderate certainty evidence to achieve continuous abstinence (CA) at late pregnancy (4 studies; 2049 women; RR=1.98, 95% CI 1.08 to 3.64, p=0.03) and low certainty evidence to achieve point prevalence abstinence (PPA) postpartum (5 studies; 2238 women; RR=1.46, 95% CI 1.05 to 2.02, p=0.02). NoMC interventions had moderate certainty evidence to achieve PPA in late pregnancy (15 studies; 16 234 women; RR=1.54, 95% CI 1.16 to 2.06, p<0.01) and low certainty evidence to achieve PPA postpartum (13 studies; 5466 women; RR=1.79, 95% CI 1.14 to 2.83, p=0.01). Both DH and BF interventions did not achieve PPA at late pregnancy, nor NoMC interventions achieve CA postpartum. The certainty was reduced due to risk of bias, heterogeneity, inconsistency and/or imprecision.

CONCLUSION

NoMC interventions can assist pregnant smokers achieve PPA and DH interventions achieve CA in late pregnancy. These interventions may achieve other outcomes.

Identification of the Obstetric Factors Increasing Tendency to Smoking Cessation During Pregnancy

INTRODUCTION

Cigarette, one of the various forms of tobacco, is the most commonly used tobacco product in Turkey and in the world. Cigarette has several negative effects on general health and is a major problem in the pregnancy period. This study aims to identify pregnancy-related factors that affect the tendency to smoking cessation and their effect levels in pregnant women who continue to smoke during pregnancy.

METHOD

The sample of this descriptive and cross-sectional study was 430 pregnant women who smoked. Data were collected through an original interview form and face-to-face interviews. Data analysis was performed using chi-square, independent t test, and multiple logistic regression model in terms of demographic, obstetric, maternal, and fetal features.

RESULTS

The average number of cigarettes smoked before pregnancy was 13.28 ± 8.62, whereas the average number of cigarettes smoked during pregnancy was 6.60 ± 7.64. The tendency to decrease smoking increases 2.8 times ( OR = 2.825, 95% CI [1.631, 4.895]) with the number of pregnancies and approximately 2 times in case of a planned pregnancy ( OR = 1.946, 95% CI [1.076, 3.520]). The frequency of having prenatal visits showed a weak but significant relationship with the number of abortuses and the number of living children.

CONCLUSIONS

Developing a risk map in line with the findings of the study and considering the obstetric features of smoking women could enable to hypothesize about the types of behaviors in smoking in the following processes of pregnancy. With the precautions to be taken, the negative effects of smoking on maternal and fetal health could be prevented or minimized.

A Comprehensive Review on Social Inequalities and Pregnancy Outcome-Identification of Relevant Pathways and Mechanisms

Scientific literature tends to support the idea that the pregnancy and health status of fetuses and newborns can be affected by maternal, parental, and contextual characteristics. In addition, a growing body of evidence reports that social determinants, measured at individual and/or aggregated level(s), play a crucial role in fetal and newborn health. Numerous studies have found social factors (including maternal age and education, marital status, pregnancy intention, and socioeconomic status) to be linked to poor birth outcomes. Several have also suggested that beyond individual and contextual social characteristics, living environment and conditions (or "neighborhood") emerge as important determinants in health inequalities, particularly for pregnant women. Using a comprehensive review, we present a conceptual framework based on the work of both the Commission on Social Determinants of Health and the World Health Organization (WHO), aimed at describing the various pathways through which social characteristics can affect both pregnancy and fetal health, with a focus on the structural social determinants (such as socioeconomic and political context) that influence social position, as well as on intermediary determinants. We also suggest that social position may influence more specific intermediary health determinants; individuals may, on the basis of their social position, experience differences in environmental exposure and vulnerability to health-compromising living conditions. Our model highlights the fact that adverse birth outcomes, which inevitably lead to health inequity, may, in turn, affect the individual social position. In order to address both the inequalities that begin in utero and the disparities observed at birth, it is important for interventions to target various unhealthy behaviors and psychosocial conditions in early pregnancy. Health policy must, then, support: (i) midwifery availability and accessibility and (ii) enhanced multidisciplinary support for deprived pregnant women.

Effects of Smoking Reduction and Cessation on Birth Outcomes in a Scheduled Gradual Reduction Cessation Trial

INTRODUCTION

Smoking during pregnancy can affect infant birthweight. We tested whether an intervention that promoted scheduled gradual reduction improved birth outcomes among pregnant women who smoked. We also examined race differences in birth outcomes.

METHODS

We conducted a 2-arm randomized controlled trial where pregnant women who smoked received either SMS text-delivered scheduled gradual smoking reduction (SGR) program plus support texts or support messages only throughout their pregnancy. The outcomes for this paper were birth outcomes including birth weight and gestational age obtained from chart review. Analyses were conducted using chi-square and t-tests in SAS.

RESULTS

We approached 2201 pregnant women with smoking history. Of the 314 women recruited into the study, 290 completed a medical release form (92%). We did not find any significant differences in birth outcomes by arm or race. The majority of participants reduced smoking by the 80%. Women who reduced more than 50% of their baseline cigarettes per day had a birth weight increase of 335 g compared to those that did not (p = 0.05). The presence of alcohol/drug use in prenatal visit notes was associated with low infant birth weight (p = 0.05).

DISCUSSION

The scheduled gradual reduction intervention did not improve birth outcomes. Additional research is needed to help improve birth outcomes for pregnant women who engage in tobacco and illicit substance use. CLINICAL TRIAL #: NCT01995097.

Maternal smoking during pregnancy and intelligence quotient of offspring aged 18 and 30 years: Evidence from two birth cohorts in southern Brazil

Maternal smoking during pregnancy causes several harmful effects, including deficits in the intelligence quotient (IQ), a measure associated with academic achievements and higher socioeconomic position. We aimed to measure the association between maternal smoking during pregnancy and offspring's IQ in two birth cohorts from Pelotas, Brazil. Data from the 1982 and 1993 birth cohorts were analyzed. Smoking during pregnancy was ascertained at the perinatal follow-up, and IQ was measured at 30 years (1982) and 18 years (1993). Simple and multiple linear regressions were used for crude and adjusted analysis. Mediation analysis was performed using birth weight and breastfeeding as possible mediators. Data analysis was conducted in 2020. There were 3611 and 4050 participants from the 1982 and 1993 cohorts, respectively. After adjustment for potential confounders, the inverse association between smoking during pregnancy and children's IQ remained significant in both cohorts. Offspring of mothers who smoked during pregnancy had an average of 1.32 less IQ points (95%CI: -2.23, -0.242) in the 1982 cohort, and an average of 1.66 less IQ points (95%CI: -2.42, -0.90) in the 1993 cohort. Neither cohort showed association with paternal smoking (negative controls) after adjustment. Breastfeeding's mediated effects accounted for 26.2% and 23.9% of the association in the 1982 and 1993 cohorts, respectively, while birth weight's accounted for 6.8% and 30.1%, respectively; indirect effects were not significant. The inverse association between maternal smoking and IQ and the lack of association with paternal smoking reinforces our findings of a negative association between exposure and outcome.

Pregnancy complications, substance abuse, and prenatal care predict birthweight in adolescent mothers

BACKGROUND

Reduced birthweight is associated with adverse physical and mental health outcomes later in life. Children of adolescent mothers are at higher risk for reduced birthweight. The current study aimed to identify the key risk factors affecting birthweight in a well-characterized sample of adolescent mothers to inform preventive public health efforts.

METHODS

Sixty-four adolescent mothers (≤ 21 years of age) provided detailed data on pregnancy, birth and psychosocial risk. Separate regression analyses with (1) birthweight and (2) low birthweight (LBW) as outcomes, and pregnancy complications, prenatal care, maternal age, substance abuse during pregnancy, socioeconomic risk, stressful life events and the child's sex as independent variables were conducted. Exploratively, a receiver operating characteristic (ROC) analysis was performed to investigate the quality of the discriminatory power of the risk factors.

RESULTS

The following variables explained variance in birthweight significantly: prenatal care attendance (p = .006), pregnancy complications (p = .006), and maternal substance abuse during pregnancy (p = .044). Prenatal care attendance (p = .023) and complications during pregnancy (p = .027) were identified as significant contributors to LBW. Substance abuse (p = .013), pregnancy complications (p = .022), and prenatal care attendance (p = .044) showed reasonable accuracy in predicting low birthweight in the ROC analysis.

CONCLUSIONS

Among high-risk adolescent mothers, both biological factors, such as pregnancy complications, and behavioural factors amenable to intervention, such as substance abuse and insufficient prenatal care, seem to contribute to reduced birthweight in their children, a predisposing factor for poorer health outcomes later in life. More tailored intervention programmes targeting the specific needs of this high-risk group are needed.

Behavioral Smoking Cessation Counseling During Pregnancy: A Cost-Effectiveness Analysis

OBJECTIVE

To examine the cost effectiveness of using behavioral smoking cessation counseling during pregnancy.

METHODS

We designed a decision-analytic model using TreeAge Pro 2020 software to compare the cost effectiveness and outcomes among women who received behavioral smoking cessation counseling compared with women who received usual care during pregnancy. We used a theoretical cohort of 285,000 women, the approximate number of pregnant women who smoke each year in the United States. Outcomes included maternal abstinence from smoking, fetal growth restriction, stillbirth, preterm delivery, neonatal death, and cerebral palsy, in addition to cost and quality-adjusted life-years (QALYs) for both the woman and the neonate. All model inputs were derived from the literature, and a willingness-to-pay threshold was set at $100,000 per QALY. Sensitivity analyses were performed to determine the robustness of baseline assumptions.

RESULTS

In our theoretical cohort, behavioral smoking cessation counseling compared with usual care was associated with 9,019 additional women stopping smoking during pregnancy (34,604 vs 25,585). Smoking cessation counseling also resulted in 911 fewer cases of fetal growth restriction, 20 fewer stillbirths, 250 fewer preterm deliveries, 11 fewer neonatal deaths, and one less case of cerebral palsy. Using behavioral smoking cessation counseling interventions during pregnancy led to better outcomes despite higher costs, with an incremental cost-effectiveness ratio of $71,658 per QALY, which was below our willingness-to-pay threshold of $100,000 per QALY, making the intervention cost effective. Sensitivity analyses demonstrated that the counseling intervention was cost effective at probabilities of smoking cessation greater than 11.6% (baseline input: 12.1%) or the cost of the behavioral intervention was less than $475.21 (baseline input: $368.78).

CONCLUSION

Behavioral smoking cessation counseling during pregnancy was associated with fewer adverse neonatal outcomes and was cost effective. Increasing utilization of such interventions and increasing insurance coverage of this care are important initiatives to improve outcomes in this at-risk population.

Trends in Tobacco Smoking in Pregnant Women: Data From French National Perinatal Surveys

Objectives: To describe maternal smoking trends in France between 1972 and 2016, and identify whether maternal characteristics associated with smoking in the 3rd trimester of pregnancy evolved between 2010 and 2016. Methods: Using French National Perinatal Surveys, we estimated proportions of smokers and the number of cigarettes smoked both just before pregnancy and during the 3rd trimester from 1972 to 2016. We used a Poisson model with robust variance to estimate prevalence ratios for smoking during pregnancy. Results: Proportions of mothers quitting smoking were relatively stable (46.0% in 1972 and 45.8% in 2016). The number of cigarettes smoked just before pregnancy and in the 3rd trimester decreased from 1995 onward. However, proportions of smokers remained high before (30.1%) and during the 3rd trimester in 2016 (16.2%). Smoking in the 3rd trimester was associated with a lower education level and lower income in both 2010 and 2016, whereas the association with age, country of birth and parity varied according to the survey year. Conclusion: Early targeted interventions are needed for smokers who plan to have a child and must take smokers' characteristics during pregnancy into account.

Nurse home visiting and prenatal substance use in a socioeconomically disadvantaged population in British Columbia: analysis of prenatal secondary outcomes in an ongoing randomized controlled trial

BACKGROUND

Nurse-Family Partnership (NFP) involves public health nurses providing frequent home visits from early pregnancy until children reach age 2 years, focusing on first-time parents experiencing socioeconomic disadvantage. Our aim was to evaluate NFP's effectiveness in improving child and maternal health.

METHODS

We conducted an analysis of prenatal secondary outcomes in an ongoing randomized controlled trial in British Columbia; the data used in this analysis were collected from January 2014 to May 2017. Participants were pregnant girls and women aged 14-24 years who were preparing to parent for the first time and experiencing socioeconomic disadvantage. They were randomly allocated 1:1 to the intervention (NFP plus existing services) or control group (existing services). Prespecified prenatal secondary outcome indicators were changes in use of nicotine cigarettes and alcohol use by 34-36-weeks' gestation. We also report on prespecified exploratory cannabis and street drug use measures. We used mixed-effect models for longitudinal and clustered data to estimate intervention effects. Analyses were by intention to treat.

RESULTS

The median gestational age at baseline for the 739 participants (368 participants in the intervention group, 371 in the comparison group) was 20 weeks, 6 days. By 34-36 weeks' gestation, NFP significantly reduced cigarette counts (over the past 2 d) (difference in changes [DIC] of count -1.6, 95% confidence interval [CI] -6.4 to -1.3) in those who smoked. NFP also significantly reduced rates of prenatal cannabis use (DIC -6.4, 95% CI -17.0 to -1.7), but not rates of street drug or "any" substance use. While we observed decreased rates of cigarette and alcohol use in both groups (DIC of proportions -2.8, 95% CI -15.3 to 0.6; DIC -0.5, 95% CI -8.7 to 1.8, respectively), these changes were not statistically significant.

INTERPRETATION

We found no evidence that NFP was effective in reducing rates of prenatal cigarette and alcohol use; however, it led to reduced prenatal cannabis use, and in smokers it led to modest reductions in cigarette use. NFP may therefore hold promise for reducing some types of prenatal substance use in disadvantaged populations. Trial registration: ClinicalTrials.gov, no. NCT01672060.

[Consequences of Active Cigarette Smoking in Pregnancy - CNGOF-SFT Expert Report and Guidelines on the management of smoking during pregnancy]

OBJECTIVE

To synthesize knowledge on the consequences of active smoking in pregnancy.

METHODS

The MedLine database, the Cochrane Library and French and foreign guidelines from 1999 to 2019 have been consulted.

RESULTS

Active maternal smoking is associated with an increased risk of first trimester complications such as early miscarriage and ectopic pregnancy with a dose-effect relationship between smoking and those risks. Active cigarette smoking during pregnancy is associated with an increased risk of certain type of birth defects, placenta abruptio, placenta previa, stillbirth and cesarean delivery. Active maternal smoking is associated with a reduced risk of pre-eclampsia. Children born to mothers who smoke are more at risk of premature birth and low birth weight with a dose-effect relationship for those two risks.

CONCLUSION

Apart from preeclampsia which is reduced in case of active maternal smoking, perinatal morbidity is increased among women who smoke during their pregnancy.

Pharmacological interventions for promoting smoking cessation during pregnancy

BACKGROUND

Tobacco smoking in pregnancy causes serious health problems for the developing fetus and mother. When used by non-pregnant smokers, pharmacotherapies (nicotine replacement therapy (NRT), bupropion, and varenicline) are effective for increasing smoking cessation, however their efficacy and safety in pregnancy remains unknown. Electronic cigarettes (ECs) are becoming widely used, but their efficacy and safety when used for smoking cessation in pregnancy are also unknown.

OBJECTIVES

To determine the efficacy and safety of smoking cessation pharmacotherapies and ECs used during pregnancy for smoking cessation in later pregnancy and after childbirth, and to determine adherence to smoking cessation pharmacotherapies and ECs for smoking cessation during pregnancy.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (20 May 2019), trial registers, and grey literature, and checked references of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) conducted in pregnant women, comparing smoking cessation pharmacotherapy or EC use with either placebo or no pharmacotherapy/EC control. We excluded quasi-randomised, cross-over, and within-participant designs, and RCTs with additional intervention components not matched between trial arms.

DATA COLLECTION AND ANALYSIS

We followed standard Cochrane methods. The primary efficacy outcome was smoking cessation in later pregnancy; safety was assessed by 11 outcomes (principally birth outcomes) that indicated neonatal and infant well-being. We also collated data on adherence to trial treatments. We calculated the risk ratio (RR) or mean difference (MD) and the 95% confidence intervals (CI) for each outcome for each study, where possible. We grouped eligible studies according to the type of comparison. We carried out meta-analyses where appropriate.

MAIN RESULTS

We included 11 trials that enrolled a total of 2412 pregnant women who smoked at enrolment, nine trials of NRT and two trials of bupropion as adjuncts to behavioural support, with comparable behavioural support provided in the control arms. No trials investigated varenicline or ECs. We assessed four trials as at low risk of bias overall. The overall certainty of the evidence was low across outcomes and comparisons as assessed using GRADE, with reductions in confidence due to risk of bias, imprecision, and inconsistency. Compared to placebo and non-placebo (behavioural support only) controls, there was low-certainty evidence that NRT increased the likelihood of smoking abstinence in later pregnancy (RR 1.37, 95% CI 1.08 to 1.74; I² = 34%, 9 studies, 2336 women). However, in subgroup analysis by comparator type, there was a subgroup difference between placebo-controlled and non-placebo controlled RCTs (test for subgroup differences P = 0.008). There was unclear evidence of an effect in placebo-controlled RCTs (RR 1.21, 95% CI 0.95 to 1.55; I² = 0%, 6 studies, 2063 women), whereas non-placebo-controlled trials showed clearer evidence of a benefit (RR 8.55, 95% CI 2.05 to 35.71; I² = 0%, 3 studies, 273 women). An additional subgroup analysis in which studies were grouped by the type of NRT used found no difference in the effectiveness of NRT in those using patches or fast-acting NRT (test for subgroup differences P = 0.08). There was no evidence of a difference between NRT and control groups in rates of miscarriage, stillbirth, premature birth, birthweight, low birthweight, admissions to neonatal intensive care, caesarean section, congenital abnormalities, or neonatal death. In one study infants born to women who had been randomised to NRT had higher rates of 'survival without developmental impairment' at two years of age compared to the placebo group. Non-serious adverse effects observed with NRT included headache, nausea, and local reactions (e.g. skin irritation from patches or foul taste from gum), but data could not be pooled. Adherence to NRT treatment regimens was generally low. We identified low-certainty evidence that there was no difference in smoking abstinence rates observed in later pregnancy in women using bupropion when compared to placebo control (RR 0.74, 95% CI 0.21 to 2.64; I² = 0%, 2 studies, 76 women). Evidence investigating the safety outcomes of bupropion use was sparse, but the existing evidence showed no difference between the bupropion and control group.

AUTHORS' CONCLUSIONS

NRT used for smoking cessation in pregnancy may increase smoking cessation rates in late pregnancy. However, this evidence is of low certainty, as the effect was not evident when potentially biased, non-placebo-controlled RCTs were excluded from the analysis. Future studies may therefore change this conclusion. We found no evidence that NRT has either positive or negative impacts on birth outcomes; however, the evidence for some of these outcomes was also judged to be of low certainty due to imprecision and inconsistency. We found no evidence that bupropion may be an effective aid for smoking cessation during pregnancy, and there was little evidence evaluating its safety in this population. Further research evidence on the efficacy and safety of pharmacotherapy and EC use for smoking cessation in pregnancy is needed, ideally from placebo-controlled RCTs that achieve higher adherence rates and that monitor infants' outcomes into childhood. Future RCTs of NRT should investigate higher doses than those tested in the studies included in this review.

Snus in pregnancy and infant birth size: a mother-child birth cohort study

Rationale

While recent studies show that maternal use of snus during pregnancy is increasing, the potential effects on infant birth size is less investigated, with conflicting results.

Objectives

We aimed to determine if maternal use of snus during pregnancy influences the infant anthropometric and proportional size measures at birth.

Methods

In 2313 mother–child pairs from the population-based, mother–child birth cohort PreventADALL (Preventing Atopic Dermatitis and ALLergies) in Norway and Sweden, we assessed nicotine exposure by electronic questionnaire(s) at 18 and 34 weeks of pregnancy, and anthropometric measurements at birth. Associations between snus exposure and birth size outcomes were analysed by general linear regression.

Results

Birthweight was not significantly different in infants exposed to snus in general, and up to 18 weeks of pregnancy in particular, when adjusting for relevant confounders including maternal age, gestational age at birth, pre-pregnancy body mass index, parity, fetal sex and maternal gestational weight gain up to 18 weeks. We found no significant effect of snus use on the other anthropometric or proportional size measures in multivariable linear regression models. Most women stopped snus use in early pregnancy.

Conclusion

Exposure to snus use in early pregnancy, with most women stopping when knowing about their pregnancy, was not associated with birth size. We were unable to conclude on effects of continued snus use during pregnancy because of lack of exposure in our cohort.

Snus use in pregnancy, reported by 7.1% of 2313 women, was not associated with infant birth size. As most women stopped snus use by 6 weeks gestational age, it was not possible to assess potential birth size effects of persistent use during pregnancy.http://bit.ly/2IG8Vnk

Aboriginal Wingadhan Birrang (woman's journey) of smoking cessation during pregnancy as they participate in the ICAN QUIT in pregnancy pilot step-wedge trial

BACKGROUND

Addressing smoking cessation during pregnancy among Aboriginal women is a national priority under the Closing the Gap campaign. There is a need to measure and report interventions to support Aboriginal women during pregnancy.

AIM

To quantitatively assess women's smoking experiences over a 12 week ICAN QUIT in Pregnancy program.

METHODS

Aboriginal women and/or women expecting an Aboriginal baby reported their smoking experiences through repeated cross-sectional survey at baseline, four weeks, and 12 weeks. Self-reported nicotine dependence measures (heaviness of smoking index, strength of urges and frequency of urges to smoke), intentions to quit smoking, quit attempts, use of nicotine replacement therapy were gathered as well as a carbon-monoxide measure at each time point.

RESULTS

Expectant mothers (n=22) of Aboriginal babies participated from six Aboriginal Community Controlled Health Services between November 2016 and July 2017. At 12 weeks women reported (n=17) low heaviness of smoking index 1.21 with high strength of urges 2.64 and frequency of urges 3.00; 12/13 (92%) reported likely/very likely to quit smoking, made a mean 1.67 number of quit attempts, three women (13.6%) quit smoking (validated); 5/16 (31%) reported using nicotine replacement therapy.

DISCUSSION

Participating women made multiple quit attempts demonstrating motivation to quit smoking. Smoking cessation interventions should be tailored to address high strength and frequency of nicotine dependence despite low consumption.

CONCLUSION

Prolonged smoking cessation support is recommended to address physical, behavioural and psychological aspect of smoking. Cessation support should address previous quitting experiences to assess smoking dependence and tailoring of support.

TRIAL REGISTRATION

Australian and New Zealand Clinicial Trials Registry (Ref #ACTRN12616001603404).

[Maternal smoking during pregnancy: A risk factor for respiratory disorders in children]

Maternal smoking during pregnancy (MSDP) is a well-established risk factor for negative pregnancy outcomes, but its negative effects on the health of the child after birth are less well known by both health professionals and the general public. Large cohort studies over the past 10 years have shown that MSDP is an independent risk factor for several childhood health problems such as e.g. obesity and smoking. A large number of recent studies and 3 meta-analyses demonstrate that MSDP is an independent risk factor of wheezing and asthma of the child exposed in utero to maternal smoking. MSDP is associated with epigenetic toxicities the currently most plausible hypothesis to explain the diversity of its postnatal negative effects. The eradication of MSDP could contribute to the reduction of health problems in the next generation, including the incidence of childhood respiratory disorders.

Implication of Oxidative Stress in Fetal Programming of Cardiovascular Disease

Lifestyle and genetic background are well known risk factors of cardiovascular disease (CVD). A third contributing factor is suboptimal fetal development, due to nutrient or oxygen deprivation, placental insufficiency, or exposure to toxic substances. The fetus adapts to adverse intrauterine conditions to ensure survival; the immediate consequence is low birth weight (LBW) and the long-term effect is an increased susceptibility to develop CVD in adult life. This process is known as Developmental Origins of Health and Disease (DOHaD) or fetal programming of CVD. The influence of fetal life for the future cardiovascular health of the individual has been evidenced by numerous epidemiologic studies in populations suffering from starvation during intrauterine life. Furthermore, experimental animal models have provided support and enabled exploring the underlying mechanisms. Oxidative stress seems to play a central role in fetal programming of CVD, both in the response of the feto-placental unit to the suboptimal intrauterine environment and in the alterations of physiologic systems of cardiovascular control, ultimately leading to disease. This review aims to summarize current knowledge on the alterations in oxidative balance in response to fetal stress factors covering two aspects. Firstly, the evidence from human studies of the implication of oxidative stress in LBW induced by suboptimal conditions during intrauterine life, emphasizing the role of the placenta. In the second part we summarize data on specific redox alterations in key cardiovascular control organs induced by exposure to known stress factors in experimental animals and discuss the emerging role of the mitochondria.

The Effect of Cigarette Smoking during Pregnancy on Endocrine Pancreatic Function and Fetal Growth: A Pilot Study

Introduction

Cigarette smoking in pregnancy is a common cause of fetal growth restriction. We aimed to investigate endocrine pancreatic function of mother–infant dyads in relation to cigarette smoking, as a possible mechanism for the poor fetal growth.

Methods

Prospective study of smoking mothers (10 cigarettes or more per day, self-reported to the midwife) and non-smoker control mothers during their first pregnancy. Insulin, glucose, C-peptide, HbA1C, fructosamine, prolactin, serotonin, and cortisol were measured in maternal blood at 24–26 weeks and in umbilical cord blood at birth. Cotinine was also measured in cord blood.

Results

Of 37 smokers and 36 non-smokers recruited, cord blood was obtainable from 38 babies (19 in each group). In utero cigarette exposure was associated with lower birthweight (3,035 ± 490 versus 3,405 ± 598 g, p = 0.005), with linear modeling of the smoking cohort showing a 41 g reduction for every increase of one cigarette smoked per day (95% CI −71 to −11 g, p = 0.010). There were no differences between groups in indices of maternal or perinatal endocrine pancreatic dysfunction. Heavier smoking independently correlated with higher maternal fasting levels of glucose (p = 0.044) and C-peptide (p = 0.011). We did not observe any significant associations between the daily number of cigarettes and any of the cord blood parameters. We also looked for differences between cohorts based on infant gender. Serotonin levels were higher in smoking mothers with male fetuses (p = 0.01 to p = 0.004).

Conclusion

Endocrine pancreatic dysfunction does not appear to be a major contributing factor to nicotine-associated fetal growth restriction. The higher serotonin levels in smoking mothers carrying male infants is of uncertain significance but could be a manifestation of gender differences in susceptibility to the long-term effects of cigarette smoking.

Prevention and Treatment of Smoking and Tobacco Use During Pregnancy in Selected Indigenous Communities in High-Income Countries of the United States, Canada, Australia, and New Zealand: An Evidence-Based Review

Tobacco smoking during pregnancy is the most important modifiable risk factor for adverse pregnancy outcomes and long-term health complications for mother and baby. Tobacco use during pregnancy has decreased in high-income countries but not in Indigenous women in Australia, New Zealand, the United States, and Canada. This evidence-based review focuses on tobacco use among Indigenous pregnant women in high-income countries that share a history of European colonization. Indigenous women are more likely to use tobacco because of socioeconomic disadvantage, social norms, and poor access to culturally appropriate tobacco cessation support. Complications arising from tobacco smoking during pregnancy, such as low birth weight, prematurity, perinatal death, and sudden infant death syndrome, are much higher in Indigenous populations. Effective approaches to cessation in pregnant nonindigenous women involves behavioral counseling, with or without nicotine replacement therapy (NRT). Higher nicotine metabolism during pregnancy and poor adherence may affect therapeutic levels of NRT. Only two randomized trials were conducted among Indigenous women: neither found a statistically significant difference in cessation rates between the treatment and comparison arms. Considerations should be given to (1) whole life course approaches to reduce tobacco use in Indigenous women, (2) prohibiting tobacco promotion and reducing access to alcohol for minors to prevent smoking initiation in Indigenous youth, and (3) training health-care professionals in culturally appropriate smoking cessation care to improve access to services. It is critical to ensure acceptability and feasibility of study designs, consult with the relevant Indigenous communities, and preempt implementation challenges. Research is needed into the effect of reducing or stopping smoking during pregnancy when using NRT on subsequent maternal and infant outcomes.

Wula (Voices) of Aboriginal women on barriers to accepting smoking cessation support during pregnancy: Findings from a qualitative study

AIM

To gather Aboriginal women's stories of smoking and becoming pregnant to identify the barriers in accepting smoking cessation support during pregnancy.

METHODS

Qualitative data were collected through use of yarning methodology between August 2015 and January 2016 by an Aboriginal Researcher with experience in social and community services. A short on-line survey was used to collect quantitative data. Interviews only recorded the therapeutic yarning process, which ranged from 9 to 45min duration, averaging 30min. Audio-recorded interviews were transcribed and independently coded. A general inductive analysis was used to determine emergent themes.

RESULTS

Twenty Aboriginal women between 17-38 years of age, who were pregnant or recently given birth, living in the Hunter New England (HNE) area took part. Eleven women were still smoking; nine had quit. Most were highly aware of the implications of smoking for their babies. Major themes identified for accepting support were: ambivalence towards a need for support, health professional advice, reduction in smoking, and attitudes to Nicotine Replacement Therapy (NRT). Women reported being advised to cut down, rather than to quit; reducing consumption may be a barrier to accepting NRT. Women recommended enhanced clinical support and Aboriginal community engagement in cessation care.

DISCUSSION/CONCLUSIONS

Aboriginal women in the HNE area reported quitting or reducing their cigarette intake during pregnancy. Health Professionals working with Aboriginal women during pregnancy should give consistent messages to quit smoking completely, and offer increased, ongoing and extensive smoking cessation support to Aboriginal mothers. Clinical practices could partner with Aboriginal communities to support the delivery of smoking cessation services.