Association between maternal smoking during pregnancy and offspring overweight in U.S.-born children

Association of secondhand smoke exposure during pregnancy with left ventricle structure and function in offspring at 4 years old: a prospective birth cohort study

BACKGROUND

The association of secondhand smoke exposure during pregnancy with childhood cardiac alterations remains insufficiently elucidated. This study aims to explore the correlation between maternal passive smoking during gestation with cardiac structure and function of offspring.

METHODS

1089 mother-offspring pairs from the Shanghai Birth Cohort were included. Information on secondhand smoke exposure during each trimester of pregnancy and baseline characteristics was documented during pregnancy via structured questionnaire. Subsequent follow-up assessments, encompassing anthropometric information and echocardiographic evaluation, were conducted from 2018 to 2021, when the children were 4 years old. Multiple linear regressions models were used to explore the association of secondhand smoke exposure during pregnancy with left ventricular measurements in early childhood.

RESULTS

Secondhand smoke exposure during pregnancy was correlated with increased left ventricle (LV) internal diameter in diastole [LVIDd; β = 0.38, 95%CI: (0.06, 0.70)] and in systole [LVIDs; β = 0.28, 95%CI: (0.02, 0.54)] adjusted for maternal and child characteristics. Specifically, maternal passive smoking in early pregnancy (≤ 12 weeks of gestation) showed a positive association with LV internal diameter in diastole [LVIDd; β = 0.46, 95%CI: (0.14, 0.79)], in systole [LVIDs; β = 0.35, 95%CI: (0.09, 0.60)], end diastolic volume [LVEDV; β = 1.45, 95%CI: (0.26, 2.63)] and end systolic volume [LVESV; β = 0.68, 95%CI: (0.18, 1.19)]. No significant association was observed between secondhand smoke exposure during pregnancy and LV function of offspring.

CONCLUSION

Secondhand smoke exposure during pregnancy was correlated with subclinical alterations in LV dimensions of offspring, especially during the early stage of pregnancy. Further research is necessary to confirm our findings and to explore the long-term effect of these cardiac changes on later cardiovascular risks.

Prenatal nicotine exposure leads to epigenetic alterations in peripheral nervous system signaling genes in the testis of the rat

BACKGROUND

Prenatal nicotine exposure (PNE) has been documented to cause numerous deleterious effects on fetal development. However, the epigenetic changes promoted by nicotine exposure on germ cells are still not well understood.

OBJECTIVES

In this study, we focused on elucidating the impact of prenatal nicotine exposure on regulatory epigenetic mechanisms important for germ cell development.

METHODS

Sprague-Dawley rats were exposed to nicotine during pregnancy and male progeny was analyzed at 11 weeks of age. Testis morphology was analyzed using frozen testis sections and expression of germ cell markers was examined by RT-qPCR; histone modifications were assessed by Western Blot (WB). DNA methylation analysis was performed by methylation-specific PCR of bisulfite converted DNA. Genome-wide DNA methylation was analyzed using Methylated DNA immunoprecipitation (MeDIP)-seq. We also carried out transcriptomics analysis of pituitary glands by RNA-seq.

RESULTS

We show that gestational exposure to nicotine reduces germ cell numbers, perturbs meiosis, affects the expression of germ line reprogramming responsive genes, and impacts the DNA methylation of nervous system genes in the testis. PNE also causes perturbation of gene expression in the pituitary gland of the brain.

CONCLUSIONS

Our data demonstrate that PNE leads to perturbation of male spermatogenesis, and the observed effects are associated with changes of peripheral nervous system signaling pathways. Alterations in the expression of genes associated with diverse biological activities such as cell migration, cell adhesion and GABA signaling in the pituitary gland underscore the complexity of the effects of nicotine exposure during pregnancy.

Associations of maternal and personal smoking with all-cause and cause-specific mortality risk and life expectancy: a prospective cohort study

OBJECTIVES

The aim of this study was to evaluate the individual and combined effects of maternal smoking during pregnancy (MSDP) and personal smoking on mortality and life expectancy.

STUDY DESIGN

A prospective cohort study based on the UK Biobank, with a median follow-up of 12.47 years.

METHODS

This study employed multivariate Cox regression to determine the relative risks of mortality from all causes and specific diseases according to maternal and/or personal smoking status and pack-years of smoking (0, 1-20, 21-30, >30). Additionally, this study estimated the additive interaction between the two exposures. Life table analyses were performed using the estimated age-specific mortality rates to forecast life expectancy.

RESULTS

Results indicated that MSDP elevated the risk of all-cause mortality (HR = 1.12, 95% CI: 1.09-1.15) and mortality due to neoplasms (HR = 1.10, 95% CI: 1.06-1.12), circulatory (HR = 1.13, 95% CI: 1.06-1.19), respiratory (HR = 1.27, 95% CI: 1.16-1.40) and digestive system diseases (HR = 1.22, 95% CI: 1.08-1.38). Notably, both multiplicative and additive interactions were observed between maternal and personal smoking, with Relative Excess Risk due to Interaction (RERI) values for mortality from all causes, neoplasms, circulatory, and respiratory diseases being 0.21, 0.22, 0.16, and 0.76, respectively. This study also found a trend towards shorter gained life expectancy when maternal smoking and increasing pack-years of personal smoking were combined.

CONCLUSIONS

In this cohort study of UK Biobank, MSDP was associated with an increased risk of all-cause mortality and reduced life expectancy, suggesting that quitting smoking during pregnancy might have health and longevity benefits for both generations.

Long-term adverse influence of smoking during pregnancy on height and body size of offspring at ten years old in the UK Biobank cohort

Background

To explore the long-term relationship between maternal smoking during pregnancy and early childhood growth in the UK Biobank cohort.

Methods

To estimate the effect of maternal smoking during pregnancy on offspring height and body size at ten years old, we performed binary logistic analyses and reported odds ratios (OR) as well as 95% confidence intervals (95%CIs). We also implemented the cross-contextual comparison study to examine whether such influence could be repeatedly observed among three different ethnicities in the UK Biobank cohort (n = 22,140 for White, n = 7094 for South Asian, and n = 5000 for Black). In particular, we conducted the sibling cohort study in White sibling cohort (n = 9953 for height and n = 7239 for body size) to control for unmeasured familial confounders.

Results

We discovered that children whose mothers smoked during pregnancy had greater risk of being shorter or plumper at age ten in the full UK Biobank White cohort, with 15.3% (95% CIs: 13.0%∼17.7%) higher risk for height and 32.4% (95%CIs: 29.5%∼35.4%) larger risk for body size. Similar associations were identified in the South Asian and Black ethnicities. These associations were robust and remained significant in the White sibling cohort (12.6% [95%CIs: 5.0%∼20.3%] for height and 36.1% [95%CIs: 26.3%∼45.9%] for body size) after controlling for family factors.

Conclusion

This study robustly confirms that maternal smoking during pregnancy can promote height deficit and obesity for offspring at ten years old. Our findings strongly encourage mothers to quit smoking during pregnancy for improving growth and development of offspring.

Quitting Smoking before and after Pregnancy: Study Methods and Baseline Data from a Prospective Cohort Study

Smoking during pregnancy and postpartum remains an important public health problem. No known prior study has prospectively examined mutual changes in risk factors and women's smoking trajectory across pregnancy and postpartum. The objective of this study was to report methods used to implement a prospective cohort (Msgs4Moms), present participant baseline characteristics, and compare our sample characteristics to pregnant women from national birth record data. The cohort study was designed to investigate smoking patterns, variables related to tobacco use and abstinence, and tobacco treatment quality across pregnancy through 1-year postpartum. Current smokers or recent quitters were recruited from obstetrics clinics. Analyses included Chi-square and independent sample t-tests using Cohen's d. A total of 62 participants (41 smokers and 21 quitters) were enrolled. Participants were Black (45.2%), White (35.5%), and multiracial (19.3%); 46.8% had post-secondary education; and most were Medicaid-insured (64.5%). Compared with quitters, fewer smokers were employed (65.9 vs 90.5%, Cohen's d = 0.88) and more reported financial strain (61.1% vs 28.6%; Cohen's d = 0.75). Women who continue to smoke during pregnancy cope with multiple social determinants of health. Longitudinal data from this cohort provide intensive data to identify treatment gaps, critical time points, and potential psychosocial variables warranting intervention.

Parental tobacco and indoor secondhand smoking exposure and the risk of offspring under-five mortality in low- and middle-income countries

Children are vulnerable to exposure of secondhand smoking (SHS) which is a major preventable cause of disease and death. This study aimed to investigate the association between parental tobacco use or SHS exposure, respectively, and under-five mortality. Data were obtained from the nationally representative and population-based Demographic and Health Surveys in low- and middle-income countries (LMICs) between 2000 and 2018. Cox proportional hazard regression models with complex survey design were conducted to examine the adjusted associations between parental smoking and SHS exposure and child under-five mortality. In the pooled analysis of parental smoking, 437 322 children were included. Compared with children whose parents are not smoking, those whose father or both parents smoked any form of tobacco had higher risks of mortality (hazard ratio [HR] = 1.08, 95% confidence interval [CI] = 1.03-1.13; HR = 1.18, 95% CI = 1.06-1.32, respectively). In addition, parental using smokeless tobacco, smoking tobacco, and using smokeless tobacco and smoking tobacco simultaneously was significantly associated with child under-five mortality (HR = 1.07, 95% CI = 1.01-1.12; HR = 1.12, 95%CI = 1.04-1.21; and HR = 1.17, 95%CI = 1.06-1.30, respectively). In the pooled analysis of SHS exposure, 605 442 children were included, and weekly and daily SHS exposure were significantly associated with child under-five mortality (HR = 1.11, 95% CI = 1.03-1.20, and HR = 1.10, 95% CI = 1.06-1.15, respectively). The results were robust in most stratification analyses and sensitivity analyses. Parental tobacco use and indoor SHS exposure were associated with increased risk of under-five mortality in LMICs. Comprehensive tobacco control programs should be considered by policymakers in LMICs to promote smoke-free environments for children.