Maternal smoking in pregnancy and birth defects: a systematic review based on 173 687 malformed cases and 11.7 million controls

Environmental factors affecting pregnancy outcomes

INTRODUCTION

Pregnancy represents a fragile period in the life of a woman, vulnerable to hazardous environmental substances which might affect maternal and fetal metabolism. The possible influence of environmental factors, including endocrine disrupting chemicals (EDCs), upon the mother and the fetus before and/or during pregnancy might be associated directly and/or indirectly to deleterious pregnancy outcomes. Because the existence of such associations would be, to our view, of major importance to the scientific community, their investigation is the scope of this critical review.

METHODS

This critical review includes in vivo animal and human studies regarding the role of environmental factors, including EDCs, on pregnancy outcomes complying with the SANRA (a scale for the quality assessment of narrative review articles) questions for narrative reviews. Studies were identified by searching the MEDLINE (PubMed and PubMed Central), the Cochrane library and the Google Scholar databases till October 2022 with the combinations of the appropriate key words (detailed environmental factors including EDCs AND detailed negative pregnancy outcomes) as well as by scanning references from already included articles and relevant reviews manually. Because environmental factors and EDCs have been associated to epigenetic alterations, special care has been given to EDC-induced transgenerational effects on pregnancy outcomes.

RESULTS

The existing evidence suggests positive associations between specific environmental factors and negative pregnancy outcomes such as ectopic pregnancies, pregnancy losses, gestational diabetes, hypertensive disorders of pregnancy, preterm births, birth defects, intrauterine growth restriction, and small or large for gestational age babies.

CONCLUSION

Environmental factors and EDCs may have a catalytic effect on the course and the outcomes of pregnancy.

Congenital diaphragmatic hernia subtypes: Comparing birth prevalence, occurrence by maternal age, and mortality in a national birth cohort

BACKGROUND

Population-based administrative data have rarely been used to compare the birth prevalence, risk factors for occurrence, and mortality of congenital diaphragmatic hernia (CDH) subtypes.

OBJECTIVES

We used a national birth cohort to identify CDH subtypes and compared their birth prevalence, relationship with maternal age after accounting for sociodemographic factors, and 1-year mortality rates.

METHODS

Linked hospital admission and death records were used to identify isolated and complex CDH cases (involving additional anomalies) among singleton livebirths in England between 2002 and 2018. The prevalence of each CDH subtype per 10,000 livebirths was estimated overall and by infant, birth and maternal characteristics. The relationship between maternal age and each subtype relative to no CDH was examined using multivariable log-binomial regression to estimate risk ratios (RRs). One-year mortality rates were examined using Kaplan-Meier curves and the hazard ratio (HR) of complex versus isolated CDH was calculated using Cox regression.

RESULTS

Among 9.5 million livebirths, we identified 1285 with isolated CDH and 1150 with complex CDH. The overall prevalence of isolated and complex CDH was 1.4 (95% confidence interval [CI] 1.3, 1.4) and 1.2 (95% CI 1.1, 1.3) per 10,000 livebirths, respectively. Only complex CDH was associated with maternal age. Compared with maternal age 25-34 years, complex CDH risk was elevated for maternal age < 20 years (RR 1.31, 95% CI 1.00, 1.72). Risk was highest for maternal age ≥ 40 years (RR 1.61, 95% CI 1.21, 2.15) although accounting for chromosomal anomalies attenuated the risk (RR 1.39, 95% CI 1.00, 1.92). The 1-year mortality rate for complex CDH (33.1%, 95% CI 30.5, 35.9) was slightly higher than for isolated CDH (29.7%, 95% CI 27.3, 32.3) (HR 1.10, 95% CI 0.96, 1.27).

CONCLUSIONS

Mechanisms of occurrence differed between and within CDH subtypes and 1-year mortality of complex CDH was slightly higher than for isolated CDH.

Impact of Antenatal Care on Perinatal Outcomes in New South Wales, Australia: A Decade-Long Regional Perspective

Low birth weight (LBW) and preterm birth are adverse perinatal outcomes that pose a significant risk to a child's healthy beginning. While antenatal care (ANC) is an established intervention for pregnancy care, little is understood about how the number and timing of ANC visits can impact these adverse health outcomes. This study aimed to examine the impact of the number and timing of ANC visits on LBW and preterm birth in a regional setting. A decade-long perinatal dataset related to singleton live births that took place in the Southern New South Wales Local Health District (SNSWLHD) was utilized. The outcomes of interest were LBW and preterm birth, and the exposure variables were based on the Australian pregnancy guidelines on the number and timing of ANC visits. A multivariable logistic regression was performed to measure the association between outcome and exposure while adjusting for potential confounders. A greater level of protection against LBW and preterm birth was observed among mothers who had an adequate number of visits, with early entry (first trimester) into ANC. The protective effect of an adequate number of ANC visits against LBW and preterm birth among mothers with late entry into ANC (third trimester) was found to be statistically non-significant.

Parental smoking and risk of hypospadias: An updated meta-analysis of observational studies

Background

Inconsistent relationships have been shown between cigarette smoking and hypospadias in offspring. The purpose of this study was to summarize epidemiological evidence to evaluate the relationship between parental smoking and the risk of hypospadias.

Methods

Up until October 2022, PubMed, EMBASE, Web of Science, and the Cochrane Library were systematically searched for qualified research. The summary RRs and 95% CIs were calculated using either a fixed-effects or a random-effects model. There were subgroup analyses undertaken to identify potential sources of heterogeneity.

Results

44 studies with 16,637,830 participants were included in our meta-analysis. Overall, maternal active smoking [risk ratio (RR) = 0.94; 95% confidence interval (CI): 0.90-0.99; P < 0.01] was significantly associated with the risk of hypospadias. And neither paternal smoking (RR = 1.00; 95% CI: 0.86-1.15) nor maternal passive smoking (RR = 0.91; 95% CI: 0.60-1.23) was associated with the risk of hypospadias.

Conclusion

Our study discovered an association between maternal active smoking and a decreased risk of hypospadias, which may be due to the effect of smoking on androgen. However, as numerous studies have proved that cigarette smoking during pregnancy increases the risk of overall birth abnormalities in offspring, quitting cigarettes before pregnancy positively influences the health of offspring and should be advocated worldwide.

Systematic review registration

[www.crd.york.ac.uk/prospero], identifier [CRD42022319378].

Prevalence and Factors Associated with Cardiovascular Lifestyle Risk Factors among Pregnant Women in Burkina Faso: Evidence from a Cross-Sectional Study

Data on lifestyle risk factors for cardiovascular diseases, such as smoking, alcohol consumption, inadequate physical activity, and insufficient consumption of fruits and vegetables, in pregnant women in Africa, are scarce. This study aimed to estimate the prevalence of cardiovascular lifestyle risk factors among pregnant women in Burkina Faso and identify their associated factors. Pregnant women who attended antenatal care services between December 2018 and March 2019 were included in this study. A modified Poisson regression model was used to estimate adjusted prevalence ratios (aPR) with a 95% confidence interval. A total of 1027 pregnant women participated in this study. The prevalence of alcohol consumption, tobacco use, inadequate physical activity, and insufficient consumption of fruits and vegetables were 10.2% [8.5-12.2], 3.0% [2.1-4.3], 79.4% [76.9-81.8], and 53.5% [50.5-56.6], respectively. The prevalence of more than one cardiovascular lifestyle risk factor in pregnant women was 50.9% [48.0-54.0]. The predictors significantly associated with more than one cardiovascular lifestyle risk factor were women over 30 years old aPR 1.26; 95% CI [1.03-1.53]), women living in fourth wealth index households (aPR 1.23; 95% CI [1.06-1.42]), in semi-urban areas (aPR 5.46; 95% CI [4.34-6.88]), and women with no occupation (aPR 1.31; 95% CI [1.18-1.44]). The prevalence of more than one cardiovascular lifestyle risk factor was high during pregnancy in Burkina Faso. Women of childbearing age should be advised on how healthy behaviors can lead to improved pregnancy outcomes.

Balsalazide Exposure During the Development of Fertilizing Sperm May Be Associated With Offspring Birth Defects

We report an association between balsalazide exposure during the development of fertilizing sperm and birth defects in offspring. Exposed offspring were approximately 8 times more likely to have a birth defect. There were no pre-existing reasons to suspect such a relationship, which should be confirmed in other data.

Adverse events of recreational cannabis use during pregnancy reported to the French Addictovigilance Network between 2011 and 2020

Cannabis is the main illicit psychoactive substance used by pregnant women in France. The aim of the present national survey was to describe adverse events (AEs) of recreational cannabis use during pregnancy reported to the French Addictovigilance Network (FAN). Spontaneous reports (SRs) of AEs related to recreational cannabis use during pregnancy were collected by the FAN between 01/01/2011 and 31/01/2021 (excluding cannabidiol and synthetic cannabinoids). Over the study period, 160 SRs involved cannabis use alone or in association with tobacco (59% of all SRs) which increased. Among the 175 maternal AEs, the most commons were psychiatric AEs experienced by 96 (64.9%) women, in particular cannabis use disorders (n = 89, 60.1%), dependence (n = 54, 36.5%) and abuse (n = 21, 14.2%). Among the 57 fetal AEs, the most common were heart rhythm disorders that affected 25 (16.9%) fetuses and intrauterine growth restriction (IUGR) (n = 20, 13.5%). Among the 140 neonatal AEs, the most common were IUGR experienced by 39 (26.3%) newborns and prematurity (n = 32, 21.6%). Twelve cases of congenital malformations were observed and 4 intrauterine/neonatal deaths. Furthermore, some of these AEs (n = 13) were unexpected. Cannabis use during pregnancy has problematic consequences for both mothers and infants who need close monitoring.

Maternal Cigarette Smoking and Cleft Lip and Palate: A Systematic Review and Meta-Analysis

A systematic review and meta-analysis to determine the association between active maternal smoking and cleft lip and palate etiology.

Medline, Embase, Web of Science and the Cochrane Library from inception to November, 2020.

Observational studies of cigarette smoking habits in pregnant women. Outcomes included cleft lip and/or palate, cleft lip  ±  palate and cleft palate only.

Publication bias analyses were performed and the Newcastle Ottawa scales were used to assess study quality. Fixed or random effect models were used in the meta-analysis, dependent on risk of statistical heterogeneity.

Forty-five studies were eligible for inclusion of which 11 were cohort and 34 were case-control studies. Sixteen studies were of sufficient standard for inclusion in the meta-analysis. The summary odds ratio for the association between smoking and cleft lip and/or palate was 1.42 (95%CI 1.27-1.59) with a population attributable fraction of 4% (95%CI 3%-5%). There was limited evidence to show a dose-response effect of smoking.

This review reports a moderate association between maternal smoking and orofacial cleft but the overall quality of the conventional observational studies included was poor. There is a need for high quality and novel research strategies to further define the role of smoking in the etiology of cleft lip and palate.

Congenital talipes equinovarus: A literature review

Congenital talipes equinovarus (CTEV) is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus. The etiology of CTEV is poorly understood, despite its incidence ranging from 0.76 to 3.49 cases per 1000 live births in Indonesia. CTEV involves the fixation of the foot in the adducts, varus, and equinus with concurrent soft tissue anomalies. Despite advances in treatment, disability often persists. Theoretical models have been proposed for neurological, vascular, connective tissue, bone, and muscular causes; however, the currently available data suggests that mild cases are associated with intrauterine position. CTEV's etiology appears to involve a hereditary component, as its prevalence varies by ethnic group. Genetic factors have been identified in 24–50% of cases, depending on the community studied. Based on a complex segregation analysis, the most plausible inheritance pattern is a single large-effect gene interacting with a polygenic background.

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CTEV is a congenital disability characterized by leg deformities in the cavus, adducts, varus, and equinus.

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In Indonesia, its incidence ranges from 0.76 to 3.49 cases per 1000 live births.

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Genetic factors have been identified in 24–50% of cases, depending on the community studied.

Association of social determinants with the severity of congenital heart disease

BACKGROUND

Congenital heart diseases are the most prevalent congenital malformations and cause greater morbi-mortality in newborns and infants. The aim of this study was to analyze the social determinants in families with children with the severity of congenital heart disease.

METHODS

Analytical cross-sectional study in 140 families of children with congenital heart disease to whom a structured survey was applied addressing topics related to family structure, health, economic conditions, exposure factors, and other social conditions relevant to the study, during 1 year.

RESULTS

In all, 53.7% of the studied population belonged to low socioeconomic levels. No association was found between the severity of the heart disease and the presence of pathological antecedents in the parents. The families resided in urban areas. Also, 28.3% of the mothers had four or fewer prenatal controls during pregnancy. Only 22% of heart diseases were diagnosed during pregnancy. It was found that exposure to cigarette and wood smoke during pregnancy, in addition to low socioeconomic status, was associated with greater severity of heart disease (RACHS-1 and STS-Score), when evaluated by pathophysiological groups (cyanotic/non-cyanotic/single ventricle).

CONCLUSIONS

Exposure to cigarette smoke, wood smoke during pregnancy, and low socioeconomic status turned out to be social determinants associated with the severity of heart disease analyzed by pathophysiological groups.

IMPACT

The social component has not been well characterized as a cause of congenital heart disease, especially in countries like ours, where the existence of gaps and social inequities have a high impact. The findings of this study could have an impact on public health to the extent that policies are implemented to reduce exposure to cigarettes, especially during pregnancy. Knowledge of these changes and their measurement in this type of pathology could open the door to the creation of policies aimed at their prevention, focusing on the local risk factors found, which can impact the disease.

Maternal pre-pregnancy/early-pregnancy smoking and risk of congenital heart diseases in offspring: A prospective cohort study in Central China

Background

Prior studies suggested that maternal smoking before and during pregnancy could be associated with increased risks of congenital heart diseases (CHDs) in offspring. However, the results were inconsistent, and the existence of a causal relationship was not confirmed. Our study aimed to estimate the associations of maternal active and passive smoking during the pre-pregnancy/early-pregnancy period with CHDs as well as its common phenotypes in offspring.

Methods

This study was based on data from a prospective cohort study conducted in Central China. A total of 49 158 eligible pregnant women between the 8th and 14th weeks of gestation were invited to join the cohort and were planned to be followed up until 3 months postpartum. The exposure of interest was maternal smoking status, including active and passive smoking status in 3 months before pregnancy as well as in early pregnancy. Self-reported maternal smoking status was ascertained via an in-person interview after recruitment. CHDs were diagnosed by pediatric cardiologists and classified according to ICD-10. Multivariable Poisson regression models were used to estimate the relative risks (RRs) with 95% confidence intervals (CIs) of all CHDs and their common phenotypes associated with maternal smoking status, adjusting for potential confounding factors identified by directed acyclic graphs.

Results

CHDs were diagnosed in 564 children. After adjusting for potential confounding factors and comparing with the unexposed groups, CHDs incidence was 165% higher (adjusted RR = 2.65; 95% CI = 1.76-3.98) in offspring exposed to maternal active smoking in 3 months before pregnancy, 69% higher (adjusted-RR = 1.69; 95% CI = 1.39-2.05) in offspring exposed to maternal passive smoking in 3 months before pregnancy, 133% higher (adjusted RR = 2.33; 95% CI = 1.46-3.70) for offspring exposed to maternal active smoking in early pregnancy, and 98% higher (adjusted-RR = 1.98; 95% CI = 1.56-2.51) for offspring exposed to maternal passive smoking in early pregnancy. More specifically, the offspring exposed to maternal active smoking in early pregnancy had the highest risk of Tetralogy of Fallot (adjusted RR = 9.84; 95% CI = 2.49-38.84). These findings were recapitulated in analyses that further adjusted for other behaviour variables apart from the characteristic being assessed and were also confirmed by sensitivity analyses.

Conclusions

Our findings add to the existing body of evidence that implicates maternal pre-pregnancy/early-pregnancy smoking as a significant risk factor for CHDs and their select phenotypes.

Factors associated with neonatal-near miss: birth cohorts in three Brazilian cities - Ribeirão Preto, Pelotas and São Luís, Brazil

The aim of this study was to investigate the association of sociodemographic factors, lifestyle, maternal reproductive profile and prenatal and childbirth care with neonatal near miss (NNM) morbidity in four birth cohorts. This study involved four population-based birth cohorts: Ribeirão Preto (RP) and São Luís (SL) (2010), Pelotas 2004 (PEL04) and 2015 (PEL15). NNM was defined when one or more of the following conditions were present: birthweight <1,500 g, 5-minute Apgar score <7, gestational age <32 weeks, and report of congenital malformations. The covariates were obtained with questionnaires applied to the puerperal women. Some particularities between cohorts were identified. In the RP and SL cohorts, factors of the more distal levels (sociodemographic, lifestyle, and reproductive profile) were associated with NNM. On the other hand, proximal factors related to healthcare were more significant for the occurrence of NNM in PEL. Only the absence of prenatal care was associated with NNM in all cohorts: RP (OR=4.27, 95%CI 2.16-8.45), SL (OR=2.32, 95%CI 1.09-4.94), PEL04 (OR=4.79, 95%CI 1.59-14.46), and PEL15 (OR=5.10, 95%CI 2.60-9.97).

Maternal Cigarette Smoking During Pregnancy and Genital Anomalies in Boys: A Register-Based Cohort and Sibling-Matched Design Study

Purpose

Cryptorchidism and hypospadias share several prenatal risk factors. However, in published studies, boys exposed to cigarette smoking during pregnancy have a higher risk of cryptorchidism and a lower risk of hypospadias. Using Danish register-based data, we revisited these findings with a cohort and sibling-matched design to investigate the potential effect of shared time-stable factors.

Patients and Methods

For the cohort study, we included 823,670 live-born, singleton boys born from 1991 to 2016. Crude and adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were estimated using Cox regression models for each genital anomaly according to maternal cigarette smoking during pregnancy. For the sibling-matched design, we included 399,258 brothers and used a stratified Cox regression model creating family-adjusted results.

Results

In the cohort study, we found a higher risk of cryptorchidism (aHR = 1.18, 95% CI: 1.12, 1.24) and a lower risk of hypospadias (aHR = 0.84, 95% CI: 0.76, 0.93) when comparing boys exposed to cigarette smoking with non-exposed, and for increasing numbers of cigarettes smoked. In comparison, the sibling-matched analyses suggested a slightly weaker association for cryptorchidism and an association of similar magnitude for hypospadias, both in the same direction as in the cohort study.

Conclusion

Shared, familial confounding does not seem to explain earlier findings of higher risk of cryptorchidism and lower risk of hypospadias.

The effect of maternal smoking and alcohol consumption on lip morphology

OBJECTIVE

To determine whether maternal smoking and/or alcohol consumption has an influence on lip morphology. Maternal smoking is a known risk factor for orofacial clefts; however, its influence on normal lip variation is unknown. Recent research regarding normal lip morphology has been contradictory.

DESIGN

Retrospective cohort study.

SETTING AND PARTICIPANTS

A total of 4747 children from the Avon Longitudinal Study of Parents and Children (ALSPAC) who each had 3D facial scans carried out at 15 years of age were included in the study.

METHODS

Each of the participants was automatically categorised regarding predetermined lip morphological traits. Questionnaires completed by their mothers identified smoking and alcohol habits during pregnancy. Logistic regression analyses were applied to determine the effect of maternal smoking and alcohol consumption on lip morphology.

RESULTS

Maternal smoking has significant effects on upper and lower lip contours, Cupid's bow, lower lip-chin shape and lower lip tone (all P < 0.05). There was also an indication of a potential epigenetic effect of smoking pre-pregnancy on upper lip contour (P = 0.0573). Alcohol consumption is significantly associated with philtrum shape, particularly when >6 units of alcohol are consumed per week (P = 0.0149, 32 weeks). Overall results suggest a deeply grooved philtrum is more likely if alcohol is consumed. Investigating the combined effect of smoking and alcohol consumption, lower lip contour (P = 0.00923) and lower lip-chin shape (P = 0.0171) are statistically significant, with lower lip contour more likely to be narrow in the midline, and lower lip-chin shape more likely to be an angular concavity.

CONCLUSION

Maternal smoking influences a number of lip traits, including a possible epigenetic effect on upper lip contour. Maternal alcohol consumption, particularly at a high level, influences philtrum shape. Maternal smoking and alcohol consumption have a combined effect on lower lip contour and lower lip-chin shape.

Women who smoke during pregnancy are more likely to be referred to an obstetrician during pregnancy and birth: results from a cohort study

Background

Women who smoke during pregnancy make less use of prenatal care; the relation of smoking behavior with the use of other forms of maternal healthcare is unknown. The objective of this study is to investigate the association between women’s smoking behavior and their use of healthcare during pregnancy, birth and six weeks postpartum.

Methods

We analyzed data from the Dutch Midwifery Case Registration System (VeCaS), period 2012–2019. We included women with a known smoking status, singleton pregnancies, and who had their first appointment before 24 weeks of gestation with the primary care midwife. We compared three groups: non-smokers, early stoppers (stopped smoking in the first trimester), and late- or non-stoppers (stopped smoking after the first trimester or continued smoking). Descriptive statistics were used to report maternal healthcare utilization (during pregnancy, birth and six weeks postpartum), statistical differences between the groups were calculated with Kruskal–Wallis tests. Multivariable logistic regression was conducted to assess the association between smoking behavior and referrals to primary, secondary or tertiary care.

Results

We included 41 088 pregnant women. The groups differed significantly on maternal healthcare utilization. The late- or non-stoppers initiated prenatal care later and had less face-to-face consultations with primary care midwives during pregnancy. Compared to the non-smokers, the early- and late- or non-stoppers were statistically signficiantly more likely to be referred to the obstetrician during pregnancy and birth. Postpartum, the early- and late- or non-stoppers were statistically signficantly less likely to be referred to the obstetrician compared to the non-smokers.

Conclusions

Although the early- and late- or non-stoppers initiated prenatal care later than the non-smokers, they did receive adequate prenatal care (according to the recommendations). The results suggest that not smoking during pregnancy may decrease the likelihood of referral to secondary or tertiary care. The large population of smokers being referred during pregnancy underlines the important role of the collaboration between healthcare professionals in primary and secondary or tertiary care. They need to be more aware of the importance of smoking as a medical and as a non-medical risk factor.

Update in Management of Craniosynostosis

LEARNING OBJECTIVES

After studying this article, the participant should be able to: 1. Understand the craniofacial dysmorphology of craniosynostosis, and the variation of each type. 2. Identify the functional concerns and learn the rationale behind timing of operative intervention. 3. Approach each dysmorphology critically and identify the operative intervention needed to improve form and function 4. Understand and address the specific issues related to syndromic craniosynostosis and be able to delineate management plan.

SUMMARY

Craniosynostosis is a condition in which premature fusion of one or more cranial sutures lead to abnormal head shape and growth restriction of the brain. Nonsyndromic craniosynostosis occurs in isolation, and usually involves a single suture, whereas syndromic craniosynostosis may involve multiple sutures and is associated with extracraniofacial findings. Although surgical management can be similar, the treatment plan must take into consideration issues specific to the syndromes. This article aims to provide a concise overview of the authors' current understanding regarding the presentation, treatment principle, surgical option, and debates in craniosynostosis.

Polycyclic aromatic hydrocarbons (PAHs) may explain the paradoxical effects of cigarette use on preeclampsia (PE)

Tobacco smoking and use of snus (smokeless tobacco) are associated with adverse effects on pregnancy and neonatal outcomes. Nicotine is considered a key toxicant involved in effects caused by both smoking and snus, while pyrolysis products including polycyclic aromatic hydrocarbons (PAHs) in cigarette smoke represents the constituents most unequally divided between these two groups of tobacco products. The aim of this review was: i) to compare the impact, in terms of relative effect estimates, of cigarette smoking and use of Swedish snus on pregnancy outcomes using similar non-tobacco user controls, and ii) to examine whether exposure to PAHs from smoking could explain possible differences in impact on pregnancy outcomes. We systematically searched MEDLINE, Embase, PsycInfo, Web of Science and the Cochrane Database of Systematic Reviews up to October 2021 and identified studies reporting risks for adverse pregnancy and neonatal outcomes associated with snus use and with smoking relative to pregnant women with no use of tobacco. Both snus use and smoking were associated with increased risk of stillbirth, preterm birth, and oral cleft malformation, with comparable point estimates. These effects were likely due to comparable nicotine exposure. We also found striking differences. While both smoking and snus increased the risk of having small for gestational age (SGA) infants, risk from maternal smoking was markedly higher as was the reduction in birthweight. In contrast, the risk of preeclampsia (PE) was markedly lower in smokers than in controls, while snus use was associated with a slightly increased risk. We suggest that PAHs acting via AhR may explain the stronger effects of tobacco smoking on SGA and also to the apparent protective effect of cigarette smoking on PE. Possible mechanisms involved include: i) disrupted endocrine control of fetal development as well as placental development and function, and ii) stress adaption and immune suppression in placenta and mother.

Maternal electronic cigarette exposure in relation to offspring development: a comprehensive review

Electronic cigarettes (e-cigarettes) have become increasingly popular in young generations in the United States. Because the adverse pregnancy outcomes associated with combustible cigarette smoking are well-recognized, many pregnant women switch to e-cigarettes believing that this alternative is low in toxic chemicals. However, most e-cigarettes contain nicotine, which can easily pass through the placenta and accumulate to a high concentration in fetal blood circulation. Studies have also detected toxic metals (eg, lead, cadmium, and nickel) in e-cigarettes, and carbonyl compounds and flavorings, which are suggested to be irritative and even carcinogenic. There are questions that need to be answered about the risks of e-cigarette exposure during pregnancy. Unfortunately, research evaluating the association between maternal e-cigarette exposure and offspring health is scarce, especially with regard to human studies. Some evidence from laboratory and animal studies, although inconsistent, showed that maternal exposure to e-cigarette vapor may lead to restricted growth of offspring. E-cigarette exposure may also have an impact on the metabolic health of offspring, manifested as distorted glucose homeostasis and energy metabolism. In addition, in utero exposure may lead to defects in respiratory, vascular, and neurologic system development. For humans, investigations mostly focused on immediate birth outcomes such as small-for-gestational-age neonates, low birthweight, and preterm birth; however, the results were inconclusive. Research also suggests that maternal e-cigarette exposure may result in compromised neurodevelopment in newborns. In summary, current evidence is insufficient to rigorously evaluate the health impacts of maternal e-cigarette use on offspring development. Future investigations are warranted.

Time-dependent effect of inhaled cigarette smoke exposure in the bleomycin-induced lung injury rat model

Cigarette smoke (CS) substances are known to induce diverse ailments such as cancer, decreased immunity, and lung diseases. Although some studies have been actively conducted to evaluate cigarette toxicity, the current animal exposure methods, that is, exposure of 28- or 90-days, require considerable research cost and lead to obscure results of the CS effects. In a previous study, we compared the effects of CS in a rat model of bleomycin (BLM) and lipopolysaccharide (LPS) induced lung disease. We determined that compared to the LPS-induced rat model, the BLM-induced rat model was more sensitive to alterations in secreting cytokines and total cell number. In the current study, we further confirmed the time-point of effective inhalation exposure by CS in the BLM-induced lung injury rat model. Using an automatic video instillator, rats were administered a single dose of 2.5 mg/kg BLM (day 1), and subsequently exposed to CS via inhalation (nose-only) 4 h/day, for 1, 2, 3, and 4 weeks. The bronchoalveolar lavage fluid (BALF) was obtained from the right lung lobes, total cell numbers were counted, and chemokine and cytokine expressions were evaluated using Enzyme-Linked Immunosorbent Assay. For the 1-week exposure, we observed a greater increase of neutrophils in the BLM + CS 300 μg/L group than in the BLM or CS 300 μg/L groups. Exposure of CS in the BLM-induced lung injury rat model enhanced the secretions of chemokines and cytokines, such as CCL2/MCP-1, CXCL2/MIP-2 and TNF-α, at 1 week. Immunohistochemistry and Hematoxylin and Eosin staining of lungs at 1-2 weeks after exposure clearly confirmed this tendency in the increased levels of CCL2/MCP-1 and TNF-α. Taken together, these results indicate that the rat model of BLM-induced lung injury is more sensitive to CS exposure than other rat models, and may be an appropriate model to evaluate the effect of CS exposure at 1-2 weeks.

Preconception Antidiabetic Drugs in Men and Birth Defects in Offspring : A Nationwide Cohort Study

BACKGROUND

Diabetes reduces semen quality and increasingly occurs during reproductive years. Diabetes medications, such as metformin, have glucose-independent effects on the male reproductive system. Associations with birth defects in offspring are unknown.

OBJECTIVE

To evaluate whether the risk for birth defects in offspring varies with preconceptional pharmacologic treatment of fathers with diabetes.

DESIGN

Nationwide prospective registry-based cohort study.

SETTING

Denmark from 1997 to 2016.

PARTICIPANTS

All liveborn singletons from mothers without histories of diabetes or essential hypertension.

MEASUREMENTS

Offspring were considered exposed if their father filled 1 or more prescriptions for a diabetes drug during the development of fertilizing sperm. Sex and frequencies of major birth defects were compared across drugs, times of exposure, and siblings.

RESULTS

Of 1 116 779 offspring included, 3.3% had 1 or more major birth defects (reference). Insulin-exposed offspring (n = 5298) had the reference birth defect frequency (adjusted odds ratio [aOR], 0.98 [95% CI, 0.85 to 1.14]). Metformin-exposed offspring (n = 1451) had an elevated birth defect frequency (aOR, 1.40 [CI, 1.08 to 1.82]). For sulfonylurea-exposed offspring (n = 647), the aOR was 1.34 (CI, 0.94 to 1.92). Offspring whose fathers filled a metformin prescription in the year before (n = 1751) or after (n = 2484) sperm development had reference birth defect frequencies (aORs, 0.88 [CI, 0.59 to 1.31] and 0.92 [CI, 0.68 to 1.26], respectively), as did unexposed siblings of exposed offspring (3.2%; exposed vs. unexposed OR, 1.54 [CI, 0.94 to 2.53]). Among metformin-exposed offspring, genital birth defects, all in boys, were more common (aOR, 3.39 [CI, 1.82 to 6.30]), while the proportion of male offspring was lower (49.4% vs. 51.4%, P = 0.073).

LIMITATION

Information on underlying disease status was limited.

CONCLUSION

Preconception paternal metformin treatment is associated with major birth defects, particularly genital birth defects in boys. Further research should replicate these findings and clarify the causation.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Association between maternal exposure to indoor air pollution and offspring congenital heart disease: a case–control study in East China

Background

Previous research suggested an association between maternal exposure to ambient air pollutants and the risk of congenital heart disease (CHD). However, the effect of individual prenatal exposure to indoor air pollutants on CHD occurrence was not reported.

Methods

We performed a hospital-based case–control study to investigate the association between personal air pollution exposure during pregnancy and the risk of CHD in offspring. A total of 44 cases and 75 controls were included from two hospitals in East China. We investigated maternal and residential environmental characteristics using a questionnaire and obtained personal indoor air samples to assess particulate matter (PM) and volatile organic compounds (VOCs) from 22–30 gestational weeks. Formaldehyde, benzene, toluene, xylene, total volatile organic compounds (TVOCs), PM_2.5, and PM₁₀ were assessed. Logistic regression was performed to assess associations and interactions between individual indoor air pollutants and CHD after adjusting for confounders. The potential residential environmental factors affecting the risks of indoor air pollutants on CHD were also assessed.

Results

Median TVOC (0.400 vs. 0.005 mg/m³, P < 0.001) exposure levels in cases were significantly higher than controls. A logistic regression model adjusted for confounders revealed that exposure to high levels of indoor TVOCs (AOR 7.09, 95% CI 2.10–23.88) during pregnancy was associated with risks for CHD and the occurrence of some major CHD subtype in offspring. These risk effects were enhanced in pregnant women living in a newly renovated house but were mitigated by household use of smoke ventilators when cooking. We observed a positive interaction of maternal exposure to TVOCs and PM_2.5 and the risk for CHD.

Conclusions

Maternal exposure to indoor VOCs and PMs may increase the risk of giving birth to foetuses with CHD.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-022-13174-0.

How Risky Are Risk Factors? An Analysis of Prenatal Risk Factors in Patients Participating in the Congenital Upper Limb Differences Registry

Purpose

Risk factors for congenital upper limb differences (CoULDs) are often studied at the general population level. The CoULD registry provides a unique opportunity to study prenatal risk factors within a large patient sample.

Methods

All patients enrolled between June 2014 and March 2020 in the prospective CoULD registry, a national multicenter database of patients diagnosed with a CoULD, were included in the analysis. We analyzed self-reported, prenatal risk factors, including maternal smoking, alcohol use, recreational drug use, prescription drug use, gestational diabetes mellitus (GDM), and gestational hypertension. The outcome measures included comorbid medical conditions, proximal involvement of limb difference, bilateral involvement, and additional orthopedic conditions. Multivariable logistic regression was used to analyze the effect of the risk factors, controlling for sex and the presence of a named syndrome.

Results

In total, 2,410 patients were analyzed, of whom 72% (1,734) did not have a self-reported risk factor. Among the 29% (676) who did have at least 1 risk factor, prenatal maternal prescription drug use was the most frequent (376/2,410; 16%). Maternal prescription drug use was associated with increased odds of patient medical comorbidities (odds ratio [OR] = 1.43, P = .02). Gestational diabetes mellitus was associated with increased odds of comorbid medical conditions (OR = 1.58, P = .04), additional orthopedic conditions (OR = 1.51, P = .04), and proximal involvement (OR = 1.52, P = .04). Overall, reporting 1 or more risk factors increased the odds of patient comorbid medical conditions (OR = 1.42, P < .001) and additional orthopedic conditions (OR = 1.25, P = .03).

Conclusions

Most caregivers (72%) did not report a risk factor during enrollment. However, reporting a risk factor was associated with patient medical and orthopedic comorbidities. Of note, GDM alone significantly increased the odds of both these outcome measures along with proximal limb differences. These findings highlight the ill-defined etiology of CoULDs but suggest that prenatal risk factors, especially GDM, are associated with a higher degree of morbidity.

Type of study/level of evidence

Prognostic III.

The clinical manifestations, molecular mechanisms and treatment of craniosynostosis

Craniosynostosis is a major congenital craniofacial disorder characterized by the premature fusion of cranial suture(s). Patients with severe craniosynostosis often have impairments in hearing, vision, intracranial pressure and/or neurocognitive functions. Craniosynostosis can result from mutations, chromosomal abnormalities or adverse environmental effects, and can occur in isolation or in association with numerous syndromes. To date, surgical correction remains the primary treatment for craniosynostosis, but it is associated with complications and with the potential for re-synostosis. There is, therefore, a strong unmet need for new therapies. Here, we provide a comprehensive review of our current understanding of craniosynostosis, including typical craniosynostosis types, their clinical manifestations, cranial suture development, and genetic and environmental causes. Based on studies from animal models, we present a framework for understanding the pathogenesis of craniosynostosis, with an emphasis on the loss of postnatal suture mesenchymal stem cells as an emerging disease-driving mechanism. We evaluate emerging treatment options and highlight the potential of mesenchymal stem cell-based suture regeneration as a therapeutic approach for craniosynostosis.

Nervous system drugs taken by future fathers and birth defects in offspring: a prospective registry-based cohort study

OBJECTIVES

To evaluate the association of paternal intake of antipsychotics, anxiolytics, hypnotics and sedatives, antidepressants, selective serotonin reuptake inhibitors (SSRIs) and (benzo)diazepines during the development of fertilising sperm with birth defects in offspring.

DESIGN

Prospective registry-based cohort study.

SETTING

Total Danish birth cohort 1997-2016 using Danish national registries.

PARTICIPANTS

All 1 201 119 Danish liveborn singletons born 1997-2016 were eligible, 39 803 (3.3%) of whom had at least one major birth defect.

EXPOSURE

Offspring were considered exposed if their father had filled at least one prescription in the relevant drug category during development of fertilising sperm (the 3 months prior to conception).

PRIMARY AND SECONDARY OUTCOME MEASURES

Primary outcome was the diagnosis, in the first year of life, of at least one major birth defect as categorised in the EUROCAT guidelines. Secondary outcome was the diagnosis, in the first year of life, of at least one major birth defect in any of the EUROCAT subcategories. Adjusted ORs (AORs) were calculated, along with their 95% CIs, adjusted for year, education, smoking status and age of the mother, and education, disposable income and age of the father.

RESULTS

This study found weak or null associations between birth defects and selected drugs. Specifically, antidepressants (17 827 exposed births) gave 3.5% birth defects (AOR 0.97 (0.89 to 1.05)). Diazepines, oxazepines, thiazepines and oxepines (as antipsychotics, 1633 offspring) gave 4.7% birth defects (AOR 1.22 (0.97 to 1.54)), attenuated to 1.13 when excluding by mothers' prescriptions. The study was well powered assuming 100% therapy adherence, while assuming 50% therapy adherence, the study remained well powered for the largest groups (SSRIs and antidepressants overall).

CONCLUSIONS

Antipsychotics, anxiolytics, hypnotics and sedatives, antidepressants, SSRIs and benzodiazepine-derived anxiolytics, when taken by the father during development of fertilising sperm, are generally safe with regard to birth defects.

Fetal Surgery for Gastroschisis—A Review with Emphasis on Minimally Invasive Procedures

(1) Background: The morbidity of gastroschisis is defined by exposure of unprotected intestines to the amniotic fluid leading to inflammatory damage and consecutive intestinal dysmotility, the viscero-abdominal disproportion which results in an abdomen too small to incorporate the herniated and often swollen intestine, and by associated pathologies, such as in complex gastroschisis. To prevent intestinal damage and to provide for growth of the abdominal cavity, fetal interventions such as amnio exchange, gastroschisis repair or covering have been evaluated in several animal models and human trials. This review aims to evaluate the reported techniques for the fetal treatment of gastroschisis by focusing on minimally invasive procedures. (2) Methods: We conducted a systematic database search, quality assessment and analyzed relevant articles which evaluate or describe surgical techniques for the prenatal surgical management of gastroschisis in animal models or human application. (3) Results: Of 96 identified reports, 42 eligible studies were included. Fetal interventions for gastroschisis in humans are only reported for EXIT procedures and amnio exchange. In animal models, particularly in the fetal sheep model, several techniques of open or minimally invasive repair of gastroschisis or covering the intestine have been described, with fetoscopic covering being the most encouraging. (4) Discussion: Although some promising minimally invasive techniques have been demonstrated in human application and animal models, most of them are still associated with relevant fetal morbidity and mortality and barely appear to be currently applicable in humans. Further research on specific procedures, instruments and materials is needed before any human application.

Placental Neutrophil Infiltration Associated with Tobacco Exposure but Not Development of Bronchopulmonary Dysplasia

Objective: In utero inflammation is associated with bronchopulmonary dysplasia (BPD) in preterm infants. We hypothesized that maternal tobacco exposure (TE) might induce placental neutrophil infiltration, increasing the risk for BPD. Study design: We compared the composite outcome of BPD and death in a prospective pilot study of TE and no-TE mothers and their infants born <32 weeks. Placental neutrophil infiltration was approximated by neutrophil gelatinase-associated lipocalin (NGAL) ELISA, and total RNA expression was analyzed via NanoString© (Seattle, WA, USA). Result: Of 39 enrolled patients, 44% were classified as tobacco exposure. No significant difference was noted in the infant’s composite outcome of BPD or death based on maternal tobacco exposure. NGAL was higher in placentas of TE vs. non-TE mothers (p < 0.05). Placental RNA analysis identified the upregulation of key inflammatory genes associated with maternal tobacco exposure. Conclusion: Tobacco exposure during pregnancy was associated with increased placental neutrophil markers and upregulated inflammatory gene expression. These findings were not associated with BPD.

Maternal smoking status during pregnancy and low birth weight in offspring: systematic review and meta-analysis of 55 cohort studies published from 1986 to 2020

BACKGROUND

Maternal smoking during pregnancy may be associated with low birth weight (LBW) in offspring and global risk estimates have not been summarized previously. We aimed to systematically explore evidence regarding maternal smoking and the LBW risk in offspring globally and examine possible causes of heterogeneity across relevant studies.

METHODS

Comprehensive search of PubMed, Ovid Embase, Ovid Medline (R), and Web of science from inception until October 2021 was carried out. A random-effects meta-analysis was used to estimate the pooled odds ratio (OR) and corresponding 95% confidence interval (CI). Restricted cubic spline analysis with three knots was used to further examine the dose-response relationship.

RESULTS

Literature searches yielded 4940 articles, of which 53 met inclusion criteria (comprising 55 independent studies). Maternal smoking during pregnancy was significantly associated with the risk of LBW in offspring (OR = 1.89, 95% CI = 1.80-1.98). Furthermore, an obvious dose-response relationship between the amount of cigarettes daily smoked in pregnancy and the risk of LBW in offspring was observed. The results of subgroup analyses indicated that the risk of maternal smoking on LBW was larger in more recently conducted studies (P = 0.020) and longer period of active smoking during pregnancy (P = 0.002). No evidence of publication bias was found.

CONCLUSIONS

In summary, maternal smoking in pregnancy was significantly associated with a higher risk of LBW in offspring on a global scale. The risk of maternal smoking on infant LBW seems to be increasing over time, and was higher with longer smoking duration throughout pregnancy and more cigarettes smoked daily.

A cross-sectional study of brownfields and birth defects

BACKGROUND

Brownfields are a multitude of abandoned and disused sites, spanning many former purposes. Brownfields represent a heterogenous yet ubiquitous exposure for many Americans, which may contain hazardous wastes and represent urban blight. Neonates and pregnant individuals are often sensitive to subtle environmental exposures. We evaluate whether residential brownfield exposure is associated with birth defects.

METHODS

Using North Carolina birth records from 2003 to 2015, we sampled 753,195 births with 39,495 defects identified. We examined defect groups and 30 distinct phenotypes. Number of brownfields within 2,000 m of the residential address at birth was summed. We utilized mixed effects multivariable logistic regression models adjusted for demographic and environmental covariates available from birth records, 2010 Census, and EPA's Environmental Quality Index to estimate odds ratios (OR) and 95% confidence intervals (CI).

RESULTS

We observed positive associations between cardiovascular and external defect groups (OR [95% CI]: 1.07 [1.02-1.13] and 1.17 [1.01-1.35], respectively) and any brownfield exposure. We also observed positive associations with atrial septal and ventricular septal defects (1.08 [1.01-1.16] and 1.15 [1.03-1.28], respectively), congenital cataracts (1.38 [0.98-1.96]), and an inverse association with gastroschisis (0.74 [0.58-0.94]). Effect estimates for several additional defects were positive, though we observed null associations for most group and individual defects. Additional analyses indicated an exposure-response relationship for several defects across levels of brownfield exposure.

CONCLUSIONS

Our results indicate that residential proximity to brownfields is associated with birth defects, especially cardiovascular and external defects. In-depth analyses of individual defects and specific contaminants or brownfield sites may reveal additional novel associations.

Genome-wide Interaction Study Implicates VGLL2 and Alcohol Exposure and PRL and Smoking in Orofacial Cleft Risk

Non-syndromic cleft lip with or without cleft palate (NSCL/P) is a common birth defect, affecting approximately 1 in 700 births. NSCL/P has complex etiology including several known genes and environmental factors; however, known genetic risk variants only account for a small fraction of the heritability of NSCL/P. It is commonly suggested that gene-by-environment (G×E) interactions may help explain some of the “missing” heritability of NSCL/P. We conducted a genome-wide G×E interaction study in cases and controls of European ancestry with three common maternal exposures during pregnancy: alcohol, smoking, and vitamin use using a two-stage design. After selecting 127 loci with suggestive 2df tests for gene and G x E effects, 40 loci showed significant G x E effects after correcting for multiple tests. Notable interactions included SNPs of 6q22 near VGLL2 with alcohol and 6p22.3 near PRL with smoking. These interactions could provide new insights into the etiology of CL/P and new opportunities to modify risk through behavioral changes.

Lifestyle in Pregnancy and Hypospadias in Sons: A Study of 85,923 Mother-Son Pairs from Two Danish Pregnancy Cohorts

Purpose

Hypospadias is one of the most frequent male congenital malformations. It remains controversial whether maternal lifestyle during pregnancy may affects the risk of having a son with hypospadias, especially for smoking with many suggesting lower risk. We assessed the individual and joint associations between maternal cigarette smoking, pre-pregnancy body mass index (BMI), alcohol consumption, binge drinking, and caffeine consumption and occurrence of hypospadias in sons.

Patients and Methods

This cohort study utilized the Danish National Birth Cohort and the Aarhus Birth Cohort, holding detailed information on lifestyle factors in early pregnancy between 1989 and 2012. The Danish health registers were used to identify boys with hypospadias, according to International Classification of Diseases. Potential confounders and covariates were identified by literature search and use of directed acyclic graphs. Missing data were handled by multiple imputation and Cox proportional hazards models were applied to analyse data.

Results

In total, 85,923 live-born singleton boys were included in the study of whom 502 (0.6%) were diagnosed with hypospadias. Maternal smoking in early pregnancy was associated with lower occurrence of hypospadias. An increase of one cigarette smoked per day was associated with lower risk of having a son with hypospadias (adjusted hazard ratio (HR) 0.97 (95% confidence interval (CI) 0.94, 1.00)). However, sub-analyses suggested that the results may be prone to unadjusted confounding. We found no association between pre-pregnancy BMI, alcohol consumption, binge drinking, or caffeine consumption and hypospadias.

Conclusion

Maternal smoking during pregnancy was associated with lower occurrence of hypospadias but we cannot exclude uncontrolled confounding. The other investigated maternal lifestyle factors were not associated with hypospadias in sons.

Maternal cigarette smoking before or during pregnancy increases the risk of birth congenital anomalies: a population-based retrospective cohort study of 12 million mother-infant pairs

BACKGROUND

The associations of maternal cigarette smoking with congenital anomalies in offspring have been inconsistent. This study aimed to clarify the associations of the timing and intensity of maternal cigarette smoking with 12 subtypes of birth congenital anomalies based on a nationwide large birth cohort in the USA.

METHODS

We used nationwide birth certificate data from the US National Vital Statistics System during 2016-2019. Women reported the average daily number of cigarettes they consumed 3 months before pregnancy and in each subsequent trimester during pregnancy. Twelve subtypes of congenital anomalies were identified in medical records. Poisson regression analysis was used to estimate the risk ratios (RRs) with 95% confidence intervals (CIs) for 12 subtypes of congenital anomalies associated with the timing (i.e., before pregnancy, and during three different trimesters of pregnancy) and intensity (i.e., number of cigarettes consumed per day) of maternal cigarette smoking.

RESULTS

Among the 12,144,972 women included, 9.3% smoked before pregnancy and 7.0%, 6.0%, and 5.7% in the first, second, and third trimester, respectively. Maternal smoking before or during pregnancy significantly increased the risk of six subtypes of birth congenital anomalies (i.e., congenital diaphragmatic hernia, gastroschisis, limb reduction defect, cleft lip with or without cleft palate, cleft palate alone, and hypospadias), even as low as 1-5 cigarettes per day. The adjusted RRs (95% CIs) for overall birth congenital anomalies (defined as having any one of the congenital malformations above significantly associated with maternal cigarette smoking) among women who smoked 1-5, 6-10, and ≥ 11 cigarettes per day before pregnancy were 1.31 (1.22-1.41), 1.25 (1.17-1.33), and 1.35 (1.28-1.43), respectively. Corresponding values were 1.23 (1.14-1.33), 1.33 (1.24-1.42), 1.33 (1.23-1.43), respectively, for women who smoked cigarettes in the first trimester; 1.32 (1.21-1.44), 1.36 (1.26-1.47), and 1.38 (1.23-1.54), respectively, for women who smoked cigarettes in the second trimester; and 1.33 (1.22-1.44), 1.35 (1.24-1.47), and 1.35 (1.19-1.52), respectively, for women who smoked cigarettes in the third trimester. Compared with women who kept smoking before and throughout pregnancy, women who never smoked had significantly lower risk of congenital anomalies (RR 0.77, 95% CI 0.73-0.81), but women who smoked before pregnancy and quitted during each trimester of pregnancy had no reduced risk (all P > 0.05).

CONCLUSIONS

Maternal smoking before or during pregnancy increased the risk of several birth congenital anomalies, even as low as 1-5 cigarettes per day. Maternal smokers who stopped smoking in the subsequent trimesters of pregnancy were still at an increased risk of birth congenital anomalies. Our findings highlighted that smoking cessation interventions should be implemented before pregnancy.

Propensity score analysis of the association between maternal exposure to second-hand tobacco smoke and birth defects in Northwestern China

Previous studies have suggested that maternal active smoking can increase the risk of birth defects, but evidence on second-hand tobacco smoke (SHS) is limited. We aimed to assess the association between maternal exposure to SHS and birth defects in a Chinese population. The data were based on a large-scale cross-sectional survey conducted in Shaanxi Province, China. Considering the characteristics of survey design and the potential impact of confounding factors, we adopted propensity score matching (PSM) to match the SHS exposure group and the non-exposure group to attain a balance of the confounders between the two groups. Subsequently, conditional logistic regression was employed to estimate the effect of SHS exposure on birth defects. Furthermore, sensitivity analyses were conducted to verify the key findings. After nearest neighbor matching of PSM with a ratio of 2 and a caliper width of 0.03, there were 6,205 and 12,410 participants in the exposure and control group, respectively. Pregnant women exposed to SHS were estimated to be 58% more likely to have infants with overall birth defects (OR = 1.58, 95% CI: 1.30-1.91) and 75% more likely to have infants with circulatory system defects (OR = 1.75, 95% CI: 1.26-2.44). We also observed that the risk effect of overall birth defects had an increasing trend as the frequency of exposure increased. Additionally, sensitivity analyses suggested that our results had good robustness. These results indicate that maternal exposure to SHS likely increases the risk of overall birth defects, especially circulatory system defects, in Chinese offspring.

Tobacco and Cannabis Use During Pregnancy

OBJECTIVES

Nicotine (NIC) use during pregnancy can influence markers used in biochemical maternal serum screening. This study was designed to determine prevalence of disclosed tobacco smokers in our patient population and to compare disclosed tobacco smoking status with the presence of serum nicotine and a common tetrahydrocannabinol (THC) metabolite.

METHODS

A deidentified dataset of disclosed smoking status for quadruple (Quad) screens was obtained. Residual serum submitted for Quad screens was obtained from frozen storage and analyzed for NIC and THC metabolites.

RESULTS

Of specimens that had corresponding responses to the smoking history question on the patient history form, 7.2% (n = 1,783 of 24,611) specified that the patient was a tobacco smoker. Of the 271 specimens biochemically analyzed for NIC and THC metabolites, disclosed tobacco smokers had the highest prevalence of detectable NIC and THC metabolites. THC product use was most prevalent in patients categorized as probable tobacco smokers based on cotinine concentrations, as well as in younger patients.

CONCLUSIONS

Prevalence and concentration of NIC and THC metabolites vary based on disclosed tobacco smoker status. Biochemical testing may increase sensitivity for the identification of NIC and THC status over self-reporting.

OUP accepted manuscript

STUDY QUESTION

Is periconceptional maternal smoking associated with embryonic morphological development in ongoing pregnancies?

SUMMARY ANSWER

Smoking during the periconceptional period is associated with a delayed embryonic morphological development which is not fully recuperated beyond the first trimester of pregnancy.

WHAT IS KNOWN ALREADY

Smoking during pregnancy decreases prenatal growth, increasing the risk of preterm birth, small for gestational age (GA) and childhood obesity.

STUDY DESIGN, SIZE, DURATION

Between 2010 and 2018, 689 women with ongoing singleton pregnancies were periconceptionally enrolled in a prospective cohort study with follow-up until 1 year after delivery.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Between 7 + 0 and 10 + 3 weeks, GA serial three-dimensional transvaginal ultrasound scans were performed. Embryonic morphological development as assessed by the Carnegie developmental stages was evaluated using Virtual Reality techniques. In the absence of fetal morphology classification methods beyond the embryonic period, fetal ultrasound measurements at around 20 weeks’ GA, and birth weight were used to assess fetal growth. Linear mixed models were used to evaluate the association between smoking and the Carnegie stages. Regarding first-trimester morphological development, we additionally stratified our findings for mode of conception. Multiple linear regression models were used to study the association between smoking, fetal growth and birth weight. To investigate to which extent delayed embryonic morphological development mediated the effect of smoking, contemporary mediation analysis was used. Adjustments were made for potential confounders and other covariates.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 689 singleton ongoing pregnancies were included and 1210 Carnegie stages were determined. Maternal periconceptional smoking represented by the number of cigarettes/day was associated with a slight non-significant delay of the Carnegie stages (β_{cigarettes/day} = −0.058, 95% CI −0.122; 0.007, P = 0.080). Smoking of ≥10 cigarettes/day showed the strongest association (β_{≥10 cigarettes/day} = −0.352, 95% CI −0.648; −0.057, P = 0.019), as reflected by a 0.9-day delay in reaching the final Carnegie stage. Stratification for mode of conception showed a stronger negative association between the number of cigarettes/day in the IVF/ICSI group (β_{cigarettes/day} = −0.126, 95% CI −0.200; −0.051, P = 0.001) compared to naturally conceived pregnancies (β_{cigarettes/day} = 0.009, 95% CI −0.093; 0.111, P = 0.867). In the IVF/ICSI group, periconceptional smoking of ≥10 cigarettes/day was associated with in a 1.6 day delay in reaching the final Carnegie stage (β_{≥10 cigarettes/day} = −0.510, 95% CI −0.834; −0.186, P = 0.002). In the second trimester, periconceptional smoking was associated with a smaller femur length (β_{cigarettes/day} = −0.077, 95% CI −0.147; −0.008, P = 0.029) and a larger head circumference (β_{1–9 cigarettes/day} = 0.290, 95% CI 0.065; 0.514, P = 0.012). Smoking was associated with a lower birth weight, with a dose-response effect (β_{cigarettes/day} = −0.150, 95% CI −0.233; −0.068, P < 0.001). Furthermore, using the unadjusted model, 40–60% of the association between smoking and fetal ultrasound parameters and 6.3% of the association between smoking and birth weight can be explained by a delayed embryonic morphology.

LIMITATIONS, REASONS FOR CAUTION

The study population was recruited from a tertiary referral center. Smoking habits were explored using self-reported questionnaires and checked for consistency by trained researchers.

WIDER IMPLICATIONS OF THE FINDINGS

This study shows that the association of periconceptional maternal smoking and human morphological development can already be detected early in the first trimester of pregnancy using embryonic morphology as outcome. One of the key messages of this study is that the delay, or dysregulation, in embryonic morphology is associated with allometric growth reflected by smaller fetal measurements at 20 weeks gestation and lower weight at birth. The delay in embryonic morphology, measured in early pregnancy, cannot be recuperated during the pregnancy. The results of this study emphasize the importance of smoking intervention programs prior to conception. More research is warranted to assess the association between periconceptional smoking cessation and embryonic development.

STUDY FUNDING/COMPETING INTEREST(S)

The work was funded by the Department of Obstetrics and Gynaecology, Erasmus MC, University Medical Centre, Rotterdam, The Netherlands. The authors declare no conflicts of interest.

TRIAL REGISTRATION NUMBER

N/A.

Environmental Exposures and Congenital Heart Disease

Congenital heart disease (CHD) is the most common congenital abnormality worldwide, affecting 8 to 12 infants per 1000 births globally and causing >40% of prenatal deaths. However, its causes remain mainly unknown, with only up to 15% of CHD cases having a determined genetic cause. Exploring the complex relationship between genetics and environmental exposures is key in understanding the multifactorial nature of the development of CHD. Multiple population-level association studies have been conducted on maternal environmental exposures and their association with CHD, including evaluating the effect of maternal disease, medication exposure, environmental pollution, and tobacco and alcohol use on the incidence of CHD. However, these studies have been done in a siloed manner, with few examining the interplay between multiple environmental exposures. Here, we broadly and qualitatively review the current literature on maternal and paternal prenatal exposures and their association with CHD. We propose using the framework of the emerging field of the exposome, the environmental complement to the genome, to review all internal and external prenatal environmental exposures and identify potentiating or alleviating synergy between exposures. Finally, we propose mechanistic pathways through which susceptibility to development of CHD may be induced via the totality of prenatal environmental exposures, including the interplay between placental and cardiac development and the internal vasculature and placental morphology in early stages of pregnancy.

Maternal occupation as a nail technician or hairdresser during pregnancy and birth defects, National Birth Defects Prevention Study, 1997-2011

OBJECTIVE

Nail technicians and hairdressers may be exposed to chemicals with potential reproductive effects. While studies have examined birth defects in children of hairdressers, those in children of nail technicians have not been evaluated. We investigated associations between selected birth defects and maternal occupation as a nail technician or hairdresser versus a non-cosmetology occupation during pregnancy.

METHODS

We analysed population-based case-control data from the multisite National Birth Defects Prevention Study, 1997-2011. Cases were fetuses or infants with major structural birth defects; controls were live-born infants without major birth defects. Expert raters classified self-reported maternal jobs as nail technician, combination nail technician-hairdresser, hairdresser, other cosmetology work or non-cosmetology work. We used logistic regression to calculate adjusted ORs and 95% CIs for associations between occupation during pregnancy and birth defects, controlling for age, smoking, education and race/ethnicity.

RESULTS

Sixty-one mothers worked as nail technicians, 196 as hairdressers, 39 as combination nail technician-hairdressers and 42 810 as non-cosmetologists. The strongest associations among nail technicians included seven congenital heart defect (CHD) groups (ORs ranging from 2.7 to 3.5) and neural tube defects (OR=2.6, CI=0.8 to 8.4). Birth defects most strongly associated with hairdressing included anotia/microtia (OR=2.1, CI=0.6 to 6.9) and cleft lip with cleft palate (OR=2.0, CI=1.1 to 3.7). All oral cleft groups were associated with combination nail technician-hairdresser work (ORs ranging from 4.2 to 5.3).

CONCLUSIONS

Small samples resulted in wide CIs. Still, results suggest associations between maternal nail technician work during pregnancy and CHDs and between hairdressing work and oral clefts.

Effects of Stress and Nativity on Maternal Antenatal Substance Use and Postnatal Mental Disorders

Background: Maternal substance use and common mental disorders (CMDs) during or after pregnancy can lead to negative health outcomes among mothers and infants. We examined whether nativity (US-born versus foreign-born) and stress levels during pregnancy were associated with antenatal substance use and postnatal CMDs. Methods: We analyzed the Boston Birth Cohort, a racially diverse cohort recruited at birth with rolling enrollment since 1998. Information on antenatal substance use (tobacco and/or alcohol use) was obtained using an in-person postpartum questionnaire (n = 6,514). Information on postnatal CMDs (depression and/or anxiety) was obtained from medical records (n = 2,052). Nativity and stress during pregnancy were self-reported. We performed multivariate logistic regression to examine how nativity and stress levels were jointly associated with antenatal substance use and postnatal CMDs. We further investigated if blacks, Hispanics, and whites were differentially at risk. Results: We found that US-born mothers were at higher risk of substance use and CMDs than their foreign-born counterparts. In analyses combining nativity and stress, being US-born with high stress was associated with increased odds of antenatal substance use (adjusted odds ratio [aOR] = 14.91, 95% confidence interval [CI]: 12.09-18.39) and postnatal CMDs (aOR = 4.09, 95% CI: 2.72-6.15) compared with foreign-born mothers with low stress. The results of the subanalyses limited to black and Hispanic women separately were similar; high stress alone was associated with fourfold increased odds of CMDs among foreign-born Hispanic mothers (aOR = 4.27, 95% CI: 1.96-9.33). Conclusions: Findings suggest that identifying and alleviating high stress among pregnant women may reduce their risk of antenatal substance use and postnatal CMDs.

Mothers of children with major congenital anomalies have increased health care utilization over a 20-year post-birth time horizon

OBJECTIVE

This population-based, matched cohort study aimed to evaluate utilization of health care services by mothers of children with major congenital anomalies (MCAs), compared to mothers of children without MCAs over a 20-year post-birth time horizon in Denmark.

METHODS

Our analytic sample included mothers who gave birth to an infant with a MCA (n = 23,927) and a cohort of mothers matched to them by maternal age, parity and infant's year of birth (n = 239,076). Primary outcomes were period prevalence and mothers' quantity of health care utilization (primary, inpatient, outpatient, surgical, and psychiatric services) stratified by their child's age (i.e., ages 0-6 = before school, ages 7-13 = pre-school + primary education, and ages 14-18 = secondary education or higher). The secondary outcome measure was length of hospital stays. Outcome measures were adjusted for maternal age at delivery, parity, marital status, income quartile, level of education in the year prior to the index birth, previous spontaneous abortions, maternal pregnancy complications, maternal diabetes, hypertension, alcohol-related diseases, and maternal smoking.

RESULTS

In both cohorts the majority of mothers were between 26 and 35 years of age, married, and employed, and 47% were primiparous. Mothers of infants with anomalies had greater utilization of outpatient, inpatient, surgical, and psychiatric services, compared with mothers in the matched cohort. Inpatient service utilization was greater in the exposed cohort up to 13 years after a child's birth, with the highest risk in the first six years after birth [adjusted risk ratio, 1.13; 95% confidence interval (CI), 1.12-1.14], with a decrease over time. Regarding the quantity of health care utilization, the greatest difference between the two groups was in inpatient service utilization, with a 39% increased rate in the exposed cohort during the first six years after birth (adjusted rate ratio, 1.39; 95% CI, 1.37-1.42). During the first 6 years after birth, mothers of children with anomalies stayed a median of 6 days (interquartile range [IQR], 3-13) in hospital overall, while the comparison cohort stayed a median of 4 days (IQR, 2-7) in hospital overall. Rates of utilization of outpatient clinics (adjusted rate ratio, 1.36; 95% CI, 1.29-1.42), as well as inpatient (adjusted rate ratio, 1.77; 95% CI, 1.68-1.87), and surgical services (adjusted rate ratio, 1.33; 95% CI, 1.26-1.41) was higher in mothers of children with multiple-organ MCAs during 0 to 6 years after birth. Among mothers at the lowest income levels, utilization of psychiatric clinic services increased to 59% and when their child was 7 to 13 years of age (adjusted rate ratio, 1.59; 95% CI, 1.24-2.03).

CONCLUSION

Mothers of infants with a major congenital anomaly had greater health care utilization across services. Health care utilization decreased over time or remained stable for outpatient, inpatient, and surgical care services, whereas psychiatric utilization increased for up to 13 years after an affected child's birth. Healthcare utilization was significantly elevated among mothers of children with multiple MCAs and among those at the lowest income levels.

Maternal smoking during pregnancy and long-term ophthalmic morbidity of the offspring

OBJECTIVE

To examine whether smoking during pregnancy is correlated with long-term ophthalmic complications of the offspring.

STUDY DESIGN

A population-based cohort analysis was performed comparing all deliveries of mothers who reported smoking during pregnancy and non-smoking mothers between 1991 and 2014 at a single tertiary medical center. Hospitalizations of the offspring up to the age of 18 years involving ophthalmic morbidities were evaluated according to a predefined set of ICD-9 codes. A Kaplan-Meier curve was used to compare cumulative hospitalization rate in exposed and unexposed offspring and a Cox proportional hazards model was used to control for confounders.

RESULTS

During the study period, 243,680 deliveries met the inclusion criteria. Of them, 2965 (1.2%) were children of smoking mothers. Ophthalmic-related hospitalizations were significantly higher in children born to smoking mothers, as compared with the non-smoking group (1.4% vs. 0.1%, p < 0.01). Specifically, these hospitalizations were due to higher rates of visual disturbance rate and ophthalmic infections. The Kaplan-Meier curve demonstrated a significant higher cumulative incidence of ophthalmic-related hospitalizations in the smoking group (log rank p < 0.001). Using a Cox proportional hazards model, controlling for potential confounders, maternal tobacco use was found to be independently associated with long-term ophthalmic morbidity of the offspring (adjusted HR = 1.51, CI 1.11-2.04).

CONCLUSION

Maternal smoking during pregnancy is an independent risk factor for long-term ophthalmic morbidity of the offspring. These results are in line with many recent studies that strongly support maternal smoking cessation during pregnancy due to high offspring morbidity risk.

Accessing specialist support to stop smoking in pregnancy: A qualitative study exploring engagement with UK-based stop smoking services

Objectives

Specialist stop smoking services can be effective for supporting women with smoking cessation during pregnancy, but uptake of these services is low. A novel theoretical approach was used for this research, aiming to identify barriers to and facilitators of engaging with specialist smoking cessation support using the Theoretical Domains Framework (TDF).

Methods

Semi‐structured interviews and a focus group (n = 28) were carried out with pregnant women who smoke/recently quit smoking, midwives and Stop Smoking in Pregnancy advisors from two local authority commissioned services in the UK. Inductive thematic analysis was used to code interview transcripts and deductive thematic analysis used to match emerging themes to TDF domains.

Results

Themes corresponded to seven domains of the TDF: Knowledge: Knowledge of available services for pregnant smokers; Environmental context and resources: Uptake of referral to cessation services by pregnant smokers; Social Influences: Smoking norms and role of others on addressing smoking in pregnancy; Beliefs about Capabilities: Confidence in delivering and accepting pregnancy smoking cessation support; Beliefs about Consequences: Beliefs about risks of smoking in pregnancy and role of cessation services; Intentions: Intentions to quit smoking during pregnancy; Emotions: Fear of judgement from healthcare professionals for smoking in pregnancy.

Conclusions

These novel findings help to specify factors associated with pregnant women’s engagement, which are useful for underpinning service specification and design by public health commissioners and service providers. Addressing these factors could help to increase uptake of cessation services and reduce rates of smoking in pregnancy.

Maternal periconceptional folic acid supplements use and fetus risk for limb defects

BACKGROUND

Associations between the periconceptional folic acid only (FAO) or multiple micronutrients containing folic acid (MMFA) supplementation and risk for limb defects are inconsistent.

OBJECTIVE

To explore the association between periconceptional folic acid supplements use and risk for limb defects, including clubfoot, polydactyly, syndactyly, and limb deficiencies.

METHODS

Data were derived from a cohort based on a pregnancy registry in a district of Beijing, China, from 2013 to 2018. Information on maternal periconceptional FAO and MMFA supplementation was collected via face-to-face interviews at first trimester. Pregnancy outcomes including limb defects were ascertained in livebirths, stillbirths, and elective pregnancy terminations and were recorded into the system. Propensity score methods were used to adjust for potential confounders.

RESULTS

A total of 63 969 women with a singleton delivery were included. The overall prevalence of limb defects was 47.5 per 10 000 (n = 63 969) singleton deliveries. Decreased prevalence of limb defects was found among FAO/MMFA users compared with women who did not take supplements (nonusers) (46.1 vs. 61.9 per 10 000 births, adjusted risk ratio [RR] 0.80, 95% confidence interval [CI] 0.56, 1.12). Compared with nonusers (n = 6462, 10.2%), women who took either FAO (n = 26 567, 42.0%) or MMFA (n = 30 259, 47.8%) had a lower risk for total clubfoot (RR 0.40, 95% CI 0.20, 0.84), and for isolated clubfoot (RR 0.41, 95% CI 0.17, 0.97). For other limb defects except clubfoot, FAO supplementation did not appear to be associated with reduced risk, while MMFA supplementation group had 30%-50% reduced risks for other limb defects. A lower risk for limb defects or isolated limb defects was found with MMFA supplementation when FAO supplementation was used as a control.

CONCLUSIONS

Maternal periconceptional supplements with either FAO or MMFA had inverse association with clubfoot in offspring, and MMFA was associated with lower risk for isolated limb defects compared with FAO.

Association between adverse pregnancy outcomes and preceding risk factors: a cross-sectional study from Nashik District, India

Background

The preconception phase of women’s life cycle is critical but comparatively ignored. The presence of health risks is judged as hazardous to the wellbeing of women and their offspring. This study aimed to estimate the prevalence of various pregnancy outcomes and assess the association between certain risk factors and adverse outcomes.

Methods

As a part of a preconception care intervention project, a baseline survey was conducted in four blocks of Nashik District, India. In this population-based cross-sectional analytical study, we compared cases in the study group (randomly selected one tribal and one non-tribal block) with those of the control group (one tribal and one non-tribal block). A comparison was also made between the tribal and non-tribal blocks in each group. All women who had a pregnancy outcome in the preceding 12 months (01 April 2017 to 31 March 2018) were interviewed. Trained Accredited Social Health Activists conducted the survey under the direct supervision of Auxiliary Nurse Midwives and Medical Officers. Multivariate analysis was carried out to find the adjusted prevalence ratio of having a particular adverse outcome because of the prespecified potential risk factors.

Results

A total of 9307 women participated in the study. The prevalence of adverse pregnancy outcomes was as follows: abortion in 4.1%, stillbirth in 1.7%, preterm birth in 4.1%, low birth weight in 13.2%, and congenital physical defect in 2.8%. Prevalence of parental consanguinity, pre-existing maternal illness at conception, heavy work during the last six months of pregnancy, tobacco consumption, alcohol consumption, direct exposure to pesticides and domestic violence during pregnancy was 18.5, 2.2, 18.7, 5.6, 0.5, 2.3, and 0.8% respectively. Risk factors associated with abortion included pre-existing illness and heavy work in the last six months of the pregnancy. Consanguinity, tobacco consumption during pregnancy and pre-existing illness were identified as risk factors for stillbirth. Significant risk factors of low birth weight were heavy work in the last six months of pregnancy, pre-existing illness and residence in a tribal area.

Conclusion

There is a need to emphasize on maternal behaviour, including tobacco consumption, and heavy work during pregnancy, as well as on parental consanguinity and pre-existing maternal illnesses, in order to achieve the best possible pregnancy outcomes.

Regional comparison of self-reported late pregnancy cigarette smoking to mass spectrometry analysis

OBJECTIVE

To report a more accurate prevalence estimate of late pregnancy nicotine exposures.

STUDY DESIGN

A cross-sectional study during a 2-month period in 2019. Participants were women delivering in any of the six county maternity hospitals who consented to universal drug testing at the time of delivery as part of routine hospital admission.

RESULTS

Of 2531 tested samples, 18.7% tested positive for high levels of cotinine indicating primary smoking or other primary use of tobacco products. Together, 33.0% of the study population tested positive for nicotine exposure during late pregnancy compared to vital records which reported 8.2% cigarette smoking during the third trimester of pregnancy and 10.5% cigarette smoking at any time during pregnancy through maternal self-report.

CONCLUSION

Captured vital birth smoking measures vastly underreport actual primary exposures to nicotine products. Vital birth data also fail to capture secondhand exposures which constitute a significant proportion of the population.

Association between the Concentrations of Metallic Elements in Maternal Blood during Pregnancy and Prevalence of Abdominal Congenital Malformations: The Japan Environment and Children's Study

Abdominal congenital malformations are responsible for early mortality, inadequate nutrient intake, and infant biological dysfunction. Exposure to metallic elements in utero is reported to be toxic and negatively impacts ontogeny. However, no prior study has sufficiently evaluated the effects of exposure to metallic elements in utero on abdominal congenital malformations. The aim of the present study was to evaluate associations between metallic elements detected in maternal blood during pregnancy and congenital abdominal malformations. Data from participants in the Japan Environment and Children’s Study was used in the present study, and contained information on singleton and live birth infants without congenital abnormalities (control: n = 89,134) and abdominal malformations (case: n = 139). Heavy metals such as mercury (Hg), lead (Pb), cadmium (Cd), and trace elements of manganese (Mn) and selenium (Se) were detected in maternal serum samples during mid- and late-gestation. Infant congenital abnormalities were identified from delivery records at birth or one month after birth by medical doctors. In a multivariate analysis adjusted to account for potential confounders, quartiles of heavy metals and trace elements present in maternal blood were not statistically correlated to the prevalence of abdominal congenital malformations at birth. This study is the first to reveal the absence of significant associations between exposure levels to maternal heavy metals and trace elements in utero and the prevalence of abdominal congenital malformations in a large cohort of the Japanese population. Further studies are necessary to investigate the impact of exposure to heavy metals and trace elements via maternal blood in offspring after birth.

Stigma Attached to Smoking Pregnant Women: A Qualitative Insight in the General French Population

INTRODUCTION

Cigarette consumption during pregnancy has major health consequences for women and unborn children. The stigma of smoking during pregnancy might hinder mothers-to-be's access to adequate healthcare and smoking cessation, especially in disadvantaged groups. This qualitative study was designed to describe extensively the public stigma associated with smoking during pregnancy.

METHOD

Participants were French adults recruited from the general population through social networks (N=100). They were asked to answer three pairs of open-ended questions regarding cognitions, emotions and behaviours elicited in the general population by pregnant smoking women. An inductive thematic analysis was performed and inter-judge agreement was computed on 30% of the corpus analysed deductively. Finally, independence (chi-square) between themes and gender, education, parenthood and smoking status was tested.

RESULTS

Themes (n=25) were defined regarding cognitions (n=9, e.g., irresponsible, thoughtless and unmindful, etc.), emotions (n=8, e.g., anger, disgust, etc.) and behaviours (n=8, e.g., inform and persuade, moralise and blame, etc.). Global inter-judge agreement was strong (κ=0.8). No difference was observed in themes according to gender, parental status or education, indicating a heterogenous awareness of stigma. However, some differences were observed according to smoking status (χ2 = 69.59, p = 0.02) (e.g., non-smokers more frequently stressed immorality).

CONCLUSION

The stigma associated with smoking during pregnancy includes various components that might be measured and targeted in interventions to improve access to adequate healthcare and smoking cessation in this specific population.

IMPLICATIONS

This qualitative study explores the stigma that the general French population attaches to pregnant women who smoke. Themes regarding cognitions (e.g., irresponsible, thoughtless and unmindful, etc.), emotions (e.g., anger, disgust, etc.) and behaviours (e.g., inform and persuade, moralise and blame, etc.) were identified. These themes could guide further research regarding scale development and anti-stigma interventions to support smoking cessation.

Nicotine-related misperceptions among faculty and students at a Midwestern dental school

PURPOSE/OBJECTIVES

To determine the perceptions about the ill-effects of nicotine in students and faculty at a Midwestern dental school. This information will help inform the school and improve teaching on this subject during a time when electronic nicotine delivery systems are increasingly popular.

METHODS

An online survey of dental students and faculty of a Midwestern dental school was deployed in November, 2020 to determine their level of misperception about the ill effects of nicotine. An online Qualtrics survey was administered to approximately 212 predoctoral students at a dental institution and approximately 100 part- and full-time faculty at the same school.

RESULTS

The response rate for faculty was 55.1% and that for students was 37.5%. The majority of faculty and students "agreed" or "strongly agreed" that nicotine causes cancer, birth defects, cardiovascular disease, oral inflammation, and Chronic Obstructive Pulmonary Disease.

CONCLUSIONS

Dental school faculty and students linked the risks of smoking tobacco to nicotine. Based on the results of this study, we feel our institution's curriculum should consider including information specific to nicotine in addition to tobacco in general.

DNA methylome perturbations: an epigenetic basis for the emergingly heritable neurodevelopmental abnormalities associated with maternal smoking and maternal nicotine exposure†

Maternal smoking during pregnancy is associated with an ensemble of neurodevelopmental consequences in children and therefore constitutes a pressing public health concern. Adding to this burden, contemporary epidemiological and especially animal model research suggests that grandmaternal smoking is similarly associated with neurodevelopmental abnormalities in grandchildren, indicative of intergenerational transmission of the neurodevelopmental impacts of maternal smoking. Probing the mechanistic bases of neurodevelopmental anomalies in the children of maternal smokers and the intergenerational transmission thereof, emerging research intimates that epigenetic changes, namely DNA methylome perturbations, are key factors. Altogether, these findings warrant future research to fully elucidate the etiology of neurodevelopmental impairments in the children and grandchildren of maternal smokers and underscore the clear potential thereof to benefit public health by informing the development and implementation of preventative measures, prophylactics, and treatments. To this end, the present review aims to encapsulate the burgeoning evidence linking maternal smoking to intergenerational epigenetic inheritance of neurodevelopmental abnormalities, to identify the strengths and weaknesses thereof, and to highlight areas of emphasis for future human and animal model research therein.