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

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

OBJECTIVES

Exposure to tobacco products during pregnancy presents a potential harm to both mother and baby. This study sought to estimate the prevalence of vaping during pregnancy and to explore the factors and outcomes associated with vaping in pregnancy.

SETTING

England.

PARTICIPANTS

Women who gave birth between 15th and 28th October 2017.

METHODS

A cross-sectional population-based postal survey of maternal and infant health, the National Maternity Survey (NMS) 2018. The prevalence of vaping and patterns of cigarette smoking were estimated, and regression analysis was used to explore associations between maternal characteristics and vaping, and between vaping and birth outcomes.

OUTCOME MEASURES

Unweighted and weighted prevalence of vaping with 95% confidence intervals, and unadjusted and adjusted relative risks or difference in means for the association of participant characteristics and secondary outcomes with vaping. Secondary outcome measures were: preterm birth, gestational age at birth, birthweight, and initiation and duration of breastfeeding.

RESULTS

A total of 4,509 women responded to the survey. The prevalence of vaping in pregnancy was 2.8% (95%CI 2.4% to 3.4%). This varied according to the pattern of cigarette smoking in pregnancy: 0.3% in never-smokers; 3.3% in ex-smokers; 7.7% in pregnancy-inspired quitters; 9.5% in temporary quitters; and 17.7% in persistent smokers. Younger women, unmarried women, women with fewer years of formal education, women living with a smoker, and persistent smokers were more likely to vape, although after adjusting for pattern of cigarette smoking and maternal characteristics, persistent smoking was the only risk factor. We did not find any association between vaping and preterm birth, birthweight, or breastfeeding.

CONCLUSIONS

The prevalence of vaping during pregnancy in the NMS 2018 was low overall but much higher in smokers. Smoking was the factor most strongly associated with vaping. Co-occurrence of vaping with persistent smoking has the potential to increase the harms of tobacco exposure in pregnant women and their infants.

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

BACKGROUND

Trends for maternal smoking rates have varied substantially across industrialized countries. The objective was to describe how the prevalence of maternal smoking evolved in Spain during 1980-2016.

METHODS

Data came from the Spanish Collaborative Study of Congenital Malformations. Our sample consisted of 40 934 mothers of newborns with no congenital defects from hospitals all across Spain. We estimated change points in trend and the mean annual change in smoking prevalence using 'joinpoint' regression. Relevant potential factors (age, country of birth, education, parity, planned pregnancy and alcohol consumption) were examined using multivariate logistic regression.

RESULTS

Maternal smoking prevalence in 1980 and 2016 were 14.3% (95% confidence interval [CI]: 11.9-17.0) and 20.4% (95% CI: 15.9-25.8). We identified four periods with distinct trends: a sharp increase during the 80s, a plateau during the 90s, a decrease starting in 2000 and a slowdown of such decrease from 2009 on. Smoking was significantly higher among young women, Spain-born, with low education, unplanned pregnancy, and alcohol consumption.

CONCLUSIONS

Currently in Spain maternal smoking remains very high. Tobacco consumption trend showed an increase during the 80s, a plateau during the 90s, and a reduction in the 2000s. Several sociodemographic and behavioural factors were associated to greater likelihood of smoking.

Challenges Experienced by Women Who Smoke During Pregnancy or Postnatally

Maternal smoking during pregnancy and maternal smoking postnatally are important public health concerns worldwide. Smoking adversely affects the woman's general health and is causally related to pregnancy complications and serious health outcomes for the child, such as stillbirth, preterm delivery, low birth weight, and sudden infant death. The purpose of this research was to examine maternal smoking through a quantitative descriptive survey of 164 women, 120 who were pregnant and 44 who were postnatal. Women experienced barriers to quitting smoking, including dealing with stress, being exposed to smokers, not being ready to quit, not knowing how to quit, not looking for or not being able to find information about smoking or quitting smoking, and lacking adequate social and healthcare provider support. On the other hand, women revealed characteristics that suggest they might have had improved potential for quitting smoking, including having negative feelings about smoking, having cut down on smoking, smoking at a low level, having made quit attempts, thinking it would not be hard to quit smoking, being in the preparation stage of behavioral change, and thinking their healthcare providers (HCPs) would help them if they decided to quit. Taken together, those findings suggest that HCPs could offer important assistance to help women achieve smoking cessation. However, more research needs to be conducted to clarify the role and effectiveness of various HCPs in smoking cessation interventions and to identify measures to strengthen their provision of such interventions.

Deprivation and mortality related to pediatric respiratory tract infection: a cohort study in 3 high-income jurisdictions

BACKGROUND

Deaths from respiratory tract infections (RTIs) in children are preventable through timely access to public health and medical interventions. We aimed to assess whether socioeconomic disparities in mortality related to pediatric RTI persisted after accounting for health status at birth.

METHODS

We compared the prevalence of and risk factors for RTI-related death in singletons aged 28 days to 4 years across Ontario (Canada), Scotland and England (jurisdictions with universal health care) using linked administrative data for 2003-2013. We estimated rates of RTI-related mortality for children living in deprived areas and those born to teenage girls; we estimated both crude rates and those adjusted for health status at birth.

RESULTS

A total of 1 299 240 (Ontario), 547 556 (Scotland) and 3 910 401 (England) children were included in the study. Across all jurisdictions, children born in the most deprived areas experienced the highest rates of RTI-related mortality. After adjustment for high-risk chronic conditions and prematurity, we observed differences in mortality according to area-level deprivation in Ontario and England but not in Scotland. In Ontario, teenage motherhood was also an independent risk factor for RTI-related mortality.

INTERPRETATION

Socioeconomic disparities played a substantial role in child mortality related to RTI in all 3 jurisdictions. Context-specific investigations around the mechanisms of this increased risk and development of programs to address socioeconomic disparities are needed.

Partner smoking influences whether mothers quit smoking during pregnancy: a prospective cohort study

OBJECTIVE

To analyse the prevalence and intensity of smoking among pregnant women and their partners, and factors associated with quitting smoking among pregnant women.

DESIGN

A prospective cohort study, starting in 2013.

SETTING

Andalusia, the south of Spain.

SAMPLE

A cohort of 486 healthy pregnant women followed-up on three occasions during pregnancy.

METHODS

Estimation of the proportions of women and partners who quit smoking at each trimester.

MAIN OUTCOME MEASURES

To determine factors associated in a multivariable model, considering sociodemographic, obstetric, anthropometric, lifestyle variables, and the smoking habits of their partners.

RESULTS

A high proportion of women quit smoking during pregnancy (61.08%; 95% confidence interval, 95% CI 53.61-68.55%). The smoking rate amongst mothers decreased from 36.06% (n = 167) before pregnancy to 14.08% (n = 65), 12.39% (n = 54), and 11.92% (n = 51) during the three pregnancy trimesters (P < 0.001), and consumption decreased from 8.71 cigarettes/day in the first trimester to 5.51 cigarettes/day in the second trimester (P < 0.001) and 5.96 cigarettes/day in third trimester (P = 0.0002 first versus third trimester). There was only a minimal decrease in the frequency of smoking among the partners, however: 38.44% (n = 178) before pregnancy, and 36.07% (n = 167), 32.72% (n = 143), and 31.85% (n = 136) during the three trimesters of pregnancy. The consumption of cigarettes did not decrease among partners: 11.75, 11.67, and 12.09 cigarettes/day (P = 0.4299 first versus second trimester; P = 0.654 first versus third trimester). Women whose partner smoked were less likely to quit (adjusted odds ratio, aOR 0.26; 95% CI 0.12-0.55).

CONCLUSIONS

About one in ten pregnant women smoked and one in four was a passive smoker. Strategies to reduce tobacco exposure in pregnancy should include a focus on partner smoking.

TWEETABLE ABSTRACT

Pregnant women quit smoking cigarettes in pregnancy. What about their partners?

Differences in growth of Canadian children compared to the WHO 2006 Child Growth Standards

BACKGROUND

To evaluate if there are departures from the WHO Child Growth Standards (WHO-CGS) in postnatal growth of healthy 'Canadian' children in Ontario up to age 2 years, including by infant feeding and ethnicity.

METHODS

We included data on 9964 healthy, singleton children born in Ontario, Canada. Smoothed weight, length and body mass index (BMI) percentile curves were generated using quantile regression for the Canadian cohort from birth to age 2 years. Differences in percentile values were calculated comparing Canadian children vs. the WHO-CGS.

RESULTS

Canadian children under age 2 years were longer than the WHO-CGS at the 10th (0.8 cm), 50th (1.3 cm) and 90th (1.9 cm) percentiles. Canadian children incrementally surpassed the WHO-CGS in weight after age 6 months, and in BMI after 9 months. By age 2 years, the 50th percentile weight of Canadian males was 823 g (95% confidence interval (CI) 680, 965) higher than the WHO-CGS 50th percentile. Weight differences were seen regardless of feeding practice, and were greatest among children of mothers born in Canada and Europe/Western nations, and least for those of East Asian/Pacific or South Asian heritage. Among Canadian breastfed males, 18% (95% CI 16, 19) of newborns and 26% (95% CI 20, 33) toddlers aged 2 years were classified by WHO-CGS as weighing >90th percentile - much higher than the expected rate of 10%. Similarities were seen for differences in BMI.

CONCLUSIONS

Healthy Canadian infants/toddlers are longer and heavier than the WHO-CGS norms. Explanations for these discrepancies require further elucidation.

Effect of Folic Acid Food Fortification in Canada on Congenital Heart Disease Subtypes

BACKGROUND

Previous studies have yielded inconsistent results for the effects of periconceptional multivitamins containing folic acid and of folic acid food fortification on congenital heart defects (CHDs).

METHODS

We carried out a population-based cohort study (N=5 901 701) of all live births and stillbirths (including late-pregnancy terminations) delivered at ≥20 weeks' gestation in Canada (except Québec and Manitoba) from 1990 to 2011. CHD cases were diagnosed at birth and in infancy (n=72 591). We compared prevalence rates and temporal trends in CHD subtypes before and after 1998 (the year that fortification was mandated). An ecological study based on 22 calendar years, 14 geographic areas, and Poisson regression analysis was used to quantify the effect of folic acid food fortification on nonchromosomal CHD subtypes (n=66 980) after controlling for changes in maternal age, prepregnancy diabetes mellitus, preterm preeclampsia, multiple birth, and termination of pregnancy.

RESULTS

The overall birth prevalence rate of CHDs was 12.3 per 1000 total births. Rates of most CHD subtypes decreased between 1990 and 2011 except for atrial septal defects, which increased significantly. Folic acid food fortification was associated with lower rates of conotruncal defects (adjusted rate ratio [aRR], 0.73, 95% confidence interval [CI], 0.62-0.85), coarctation of the aorta (aRR, 0.77; 95% CI, 0.61-0.96), ventricular septal defects (aRR, 0.85; 95% CI, 0.75-0.96), and atrial septal defects (aRR, 0.82; 95% CI, 0.69-0.95) but not severe nonconotruncal heart defects (aRR, 0.81; 95% CI, 0.65-1.03) and other heart or circulatory system abnormalities (aRR, 0.98; 95% CI, 0.89-1.11).

CONCLUSIONS

The association between food fortification with folic acid and a reduction in the birth prevalence of specific CHDs provides modest evidence for additional benefit from this intervention.

Blogging to Quit Smoking: Sharing Stories from Women of Childbearing Years in Ontario

This study examined the degree to which the pregnant or postpartum women, in the process of quitting smoking, felt that writing in a blog about their smoking cessation journeys helped them in their efforts to become or remain smoke free. Five women who blogged for Prevention of Gestational and Neonatal Exposure to Tobacco Smoke (a website designed to help pregnant and postpartum women quit smoking) were interviewed about their experiences as bloggers. Participants were asked to complete an online survey, which had closed-ended questions regarding their sociodemographic and smoking characteristics. Once they completed the survey, semistructured qualitative interviews were conducted over the phone. Findings suggest that blogging might combine several evidence-based behavioral strategies for tobacco cessation, such as journaling and getting support from others who use tobacco. Being part of a blogging community of women who have experienced or are experiencing similar challenges can be therapeutic and help women gain confidence in their ability to quit smoking. In conclusion, blogging may help pregnant and postpartum women quit smoking by increasing their social support and promoting self-reflection.

Secular trends in smoking during pregnancy according to income and ethnic group: four population-based perinatal surveys in a Brazilian city

OBJECTIVES

To assess socioeconomic and ethnic inequalities in smoking during pregnancy over three decades (1982-2011).

SETTING

Population-based study in Pelotas City, Brazil.

PARTICIPANTS

All urban women giving birth in the city hospitals in 1982 (5909), 1993 (5223) and 2004 (4201), plus all urban and rural women delivering from January 2011 to April 2012 (6275).

PRIMARY OUTCOME

Self-reported smoking during pregnancy.

RESULTS

The prevalence of smoking during pregnancy fell from 35.7% in 1982 to 21.0% in 2011. In each survey, prevalence decreased with increasing income (p<0.001). In the poorest quintile, smoking fell by 27.4% in the period studied compared to 67.1% in the wealthiest quintile. In all surveys, prevalence was lower among white women than among those who classified themselves as black or brown (p<0.001). Over time, smoking declined by 50.0% among the former and 30.7% among the latter. Absolute and relative inequalities both increased over time.

CONCLUSIONS

The reduction in smoking during pregnancy was primarily due to a decline among white, high-income women. Further efforts are needed to reduce smoking among all population groups.