Maternal smoking during pregnancy and type 1 diabetes in the offspring: A nationwide register-based study with family-based designs

Objectives: Maternal smoking during pregnancy is associated with a reduced risk of type 1 diabetes (T1D) in the offspring. We investigated whether this association is consistent with a causal interpretation by accounting for familial (shared genetic and environmental) factors using family-based, quasi-experimental designs. Design: A nationwide, prospective cohort study and a nested case-control study (quasi-experiment) comparing children with T1D to their age-matched siblings (or cousins). Setting: Swedish national registers. Participants: We included 2,995,321 children born in Sweden between 1983 and 2014. Exposure: Information on maternal smoking during pregnancy was retrieved from the Swedish Medical Birth Register. Main outcome measures: Children were followed for a diagnosis of T1D until 2020 through the National Patient, Diabetes and Prescribed Drug Registers. Results: A total of 18,617 children developed T1D, with a median age at diagnosis of 9.4 years. The sibling and cousin comparison design included 14,284 and 7,988 of these children, respectively. Maternal smoking during pregnancy was associated with a 22% lower risk of offspring T1D in the full cohort (hazard ratio: 0.78, 95% confidence interval [CI]: 0.75 to 0.82) in the multivariable-adjusted model. The corresponding odds ratio was 0.78 (95% CI: 0.69 to 0.88) in the sibling and 0.72 (95% CI: 0.66 to 0.79) in the cousin comparison analysis. Conclusions: This nationwide, family-based study provides support for a protective effect of maternal smoking on offspring T1D. Mechanistic studies are needed to elucidate the underlying pathways behind this link.

Prenatal origins of suicide mortality: A prospective cohort study in the United States

Most suicide research focuses on acute precipitants and is conducted in high-risk populations. Yet, vulnerability to suicide is likely established years prior to its occurrence. In this study, we aimed to investigate the risk of suicide mortality conferred by prenatal sociodemographic and pregnancy-related factors. Offspring of participants (N = 49,853) of the Collaborative Perinatal Project, a U.S. population-based cohort of pregnancies enrolled between 1959 and 1966, were linked to the U.S. National Death Index to determine their vital status by the end 2016. We examined associations between sociodemographic factors during pregnancy, pregnancy complications, labor and delivery complications, and neonatal complications with suicide death coded according to ICD-9/10 criteria. By the end of 2016, 3,555 participants had died. Of these, 288 (214 males, 74 females) died by suicide (incidence rate = 15.6 per 100,000 person-years, 95% Confidence Interval [CI] = 13.9–17.5). In adjusted models, male sex (Hazard Ratio [HR] = 2.98, CI: 2.26–3.93), White race (HR = 2.14, CI = 1.63–2.83), low parental education (HR = 2.23, CI = 1.38–3.62), manual parental occupation (HR = 1.38, CI = 1.05–1.82), being a younger sibling (HR = 1.52, CI = 1.10–2.11), higher rates of pregnancy complications (HR = 2.36, CI = 1.08–5.16), and smoking during pregnancy (HR = 1,28, CI = 0.99–1.66) were independently associated with suicide risk, whereas birth and neonatal complications were not. Consistent with the developmental origins of psychiatric disorders, vulnerability to suicide mortality is established early in development. Both sociodemographic and pregnancy factors play a role in this risk, which underscores the importance of considering life course approaches to suicide prevention, possibly including provision of high-quality prenatal care, and alleviating the socioeconomic burdens of mothers and families.

Isolation, Marginalisation and Disempowerment – Understanding How Interactions with Health Providers Can Influence Smoking Cessation in Pregnancy

BackgroundMaternal smoking during pregnancy can lead to serious adverse health outcomes for both women and their infants. While smoking in pregnancy has declined over time, it remains consistently higher in women with lower socioeconomic circumstances. Furthermore, fewer women in this group will successfully quit during pregnancy. AimThis study explores the barriers to smoking cessation experienced by socially disadvantaged pregnant women and investigates how interactions with health providers can influence their smoking cessation journey.Methodsomen (either pregnant or birthed in the previous 10 years, who smoked or quit smoking in pregnancy) were recruited from a metropolitan public hospital antenatal clinic in South Australia and community organisations in surrounding suburbs. Seventeen women participated in qualitative semi-structured small focus groups or interviews. The focus groups and interviews were recorded, transcribed and thematically analysed. FindingsFour interconnected themes were identified: 1) smoking embedded in women’s challenging lives and pregnancies, 2) cyclic isolation and marginalisation, 3) feeling disempowered, and 4) autonomy and self-determination. Themes 3 and 4 are characterised as being two sides of a single coin in that they coexist simultaneously and are inseparable. A key finding is a strong unanimous desire for smoking cessation in pregnancy but women felt they did not have the necessary support from health providers or confidence and self-efficacy to be successful.ConclusionWomen would like improvements to antenatal care that increase health practitioners’ understanding of the social and contextual healthcare barriers faced by women who smoke in pregnancy. They seek assistance from health providers to make informed choices about smoking cessation and would like women-centred care. Women feel that with greater support, consistency and encouragement from health providers they could be more successful at antenatal smoking cessation.

An obstetric outcome in pregnant women with consumption of tobacco

Background: Tobacco is known to be an established cause of adverse pregnancy outcome. Scientific studies, encompassing various ethnic groups, cultures and countries, have shown that cigarette smoking during pregnancy significantly affects mother, unborn fetus and the newborn baby.Methods: A hospital based cross sectional study was performed on 933 patients, separated in two groups: tobacco users and tobacco non-users and findings from each group were compared.Results: Incidence of complications like anemia, PIH and abruption increase with maternal usage of tobacco during pregnancy, chances of preterm delivery and ectopic pregnancy was raised, rate of wound complication was more in tobacco user women. There was no significant difference in mode of delivery.Conclusions: In the present study may establish association of tobacco consumption with adverse neonatal and obstetrics outcome and may encourage administration to focus on IEC (information, education, communication) to reduce tobacco consumption during pregnancy. Incidence of complications like anemia, PIH, abruption increase with maternal usage of tobacco during pregnancy. Chances of preterm delivery and ectopic pregnancy, was raised usage with of tobacco.

Smoking influence on early and late fetal growth

Objectives Smoking during pregnancy is a leading and modifiable risk factor for fetal growth restriction (FGR) and low birthweight (<10th centile). We studied the effects of smoking in the development of early and late FGR or low birthweight, as well as in uteroplacental and fetoplacental hemodynamics of growth-restricted fetuses. Methods Retrospective cohort study of 5,537 consecutive singleton pregnancies delivered at ≤34 + 0 (“early delivery” group, n=95) and >34 + 0 (“late delivery” group, n=5,442) weeks of gestation. Each group was divided into smokers and non-smokers. Prenatal diagnosis of FGR was based on customized fetal growth standards and fetal Doppler, and postnatal birthweight was assessed using the Olsen newborn chart. Results There were 15/95 (15.8%) and 602/5,442 (11.1%) smokers in the early and late delivery groups, respectively. In early deliveries, FGR was diagnosed in 3/15 (20%) of smokers and in 20/80 (25%) of non-smokers (p=0.68). We also found no differences in birthweights and hemodynamics. In late deliveres, FGR was detected in 30/602 (5%) smokers and 64/4,840 (1.3%) non-smokers (p<0.001). Birthweights <3rd centile and <10th centile were more common in smokers vs. non-smokers: 38/602 (6.3%) vs. 87/4,840 (1.8%) and 89/602 (14.8%) vs. 288/4,840 (6%), respectively (all p<0.01). Fetal Doppler of late FGR showed slightly higher umbilical artery resistances in smokers. Conclusions Smoking in pregnancy is associated with FGR, low birthweight and higher umbilical artery Doppler resistances after 34 weeks of gestation, but we could not confirm this association in earlier deliveries.

Benefits of not smoking during pregnancy for non-Aboriginal women and their babies in New South Wales, Australia: a record linkage study

BackgroundSmoking rates among pregnant women in New South Wales (NSW) have plateaued at 8-9%. To inform relevant smoking reduction efforts, we aimed to quantify the benefits of not smoking during pregnancy for non-Aboriginal NSW mothers and their babies. The benefits of not smoking during pregnancy for NSW Aboriginal mothers have previously been described. These data are important inputs in modelling health and economic impacts of smoking cessation interventions. MethodsThis population-based cohort study used linked-data from routinely collected data sets. Not smoking during pregnancy was the exposure of interest among all NSW non-Aboriginal women who became mothers of singleton babies in 2012-2016. Unadjusted and adjusted relative risks (aRR) were used to examine associations between not smoking during pregnancy and adverse outcomes including severe morbidity, inter-hospital transfer, perinatal death, preterm birth and small-for-gestational age. Population attributable fractions (PAFs) were calculated to quantify adverse perinatal outcomes avoided in the population if all mothers were non-smokers. ResultsCompared with babies born to mothers who smoked during pregnancy, babies born to non-smoking mothers had a lower risk of all adverse perinatal outcomes including perinatal death (aRR}=0.68, 95%CI 0.61-0.76), preterm birth (aRR=0.58, 95%CI 0.56-0.61) and small-for-gestational age (aRR=0.48, 95%CI 0.47-0.50). PAFs(%) were 3.9% for perinatal death, 5.6% for preterm birth and 7.3% for small-for-gestational-age. Compared with women who smoked during pregnancy (n=36,518), those who did not smoke (n=413,072) had a lower risk of suffering severe maternal morbidity (aRR=0.87, 95%CI 0.81-0.93) and being transferred to another hospital (aRR=0.92, 95%CI 0.86-0.99). ConclusionsMothers who reported not smoking during pregnancy had a small reduction in their risk of morbidity and of being transferred to another hospital whilst their babies had substantially reduced risks of all adverse perinatal outcomes. Results have implications for clinician training, clinical care standards, and performance management.

Renewed Attention Needed for Prevention of Sudden Unexpected Death in Infancy in the Netherlands

Background: The incidence of sudden unexpected death in infancy (SUDI), which includes sudden infant death syndrome (SIDS), has declined in developed countries since the 1980s, including the Netherlands. To identify improvement opportunities in SUDI prevention, we monitored the adherence of parents to the prevention advice on infant care habits over the past 20 years, especially in relation to the SUDI incidence over time. Potential changes in parental adherence between the latest surveys are of specific interest, as these indicate where current focus is needed.Methods: Description of the prevalence of infant care factors related to the risk of SUDI, assessed from five Dutch national surveys from 1999 to 2017 among parents of infants under 12 months, and analysis of the potential differences in these prevalences between the two latest surveys in 2010/11 and 2017 with a z-test.Results: Supine sleeping position decreased from the highest prevalence of 92% in 2010/11, to 83% in 2017. Sleep sack use has increased to 55%, the highest prevalence up to now. Avoiding a duvet has remained reasonably stable since 2002/03 and now 95% of parents do not use a duvet. The prevalence of room-sharing, without sharing the bed, increased from 14% in 1999 to the highest prevalence in 2017 (31%). However, also bed-sharing almost doubled from 5.6% in 2010/11 to 10% in 2017. Breastfeeding decreased between 1999 and 2010/11, but increased from 34% in 2010/11 to 42% in 2017. An increased prevalence of mothers who abstained from smoking during pregnancy, as well as both parents not smoking, was observed, although mostly higher educated parents showed this beneficial behavior.Discussion and Conclusion: Much has already been achieved first by decreasing prone sleeping since the 80's, and subsequently promoting supine as the safest sleep position. The decrease in duvet use and smoking, and an increase in breastfeeding have also had impact. Indications of a recent decreased prevalence of the supine sleeping position and higher prevalence of bed-sharing might relate to the slightly increasing SUDI incidence in the Netherlands. Renewed attention for prevention of SUDI and specific advice targeting high-risk groups is needed. Modern, picture driven information via internet is recommended.

Factors associated with breastfeeding initiation and continuation in Canadian-born and non-Canadian-born women: a multi-centre study

Objective: To identify factors associated with breastfeeding initiation and continuation in Canadian-born and non-Canadian-born women. Design: Prospective cohort of mothers and infants born from 2008–2012: the CHILD Cohort Study. Setting: General community setting in four Canadian provinces. Participants: 3455 pregnant women from Vancouver, Edmonton, Winnipeg, and Toronto between 2008 and 2012. Results: Of 3010 participants included in this study, the majority were Canadian-born (75.5%). Breastfeeding initiation rates were high in both non-Canadian-born (95.5%) and Canadian-born participants (92.7%). The median breastfeeding duration was 10 months in Canadian-born participants and 11 months in non-Canadian-born participants. Among Canadian-born participants, factors associated with breastfeeding initiation and continuation were older maternal age, higher maternal education, living with their partner, and recruitment site. Rooming-in during the hospital stay was also associated with higher rates of breastfeeding initiation, but not continuation at 6-months postpartum. Factors associated with non-initiation of breastfeeding and cessation at 6-months postpartum were maternal smoking, living with a current smoker, cesarean birth, and early-term birth. Among non-Canadian-born participants, maternal smoking during pregnancy was associated with lower odds of breastfeeding initiation, and lower odds of breastfeeding continuation at 6 months, and older maternal age and recruitment site were associated with breastfeeding continuation at 6 months. Conclusions: Although Canadian-born and non-Canadian-born women in the CHILD cohort have similar breastfeeding initiation rates, breastfeeding initiation and continuation are more strongly associated with sociodemographic characteristics in Canadian-born participants. Recruitment site was strongly associated with breastfeeding continuation in both groups and may indicate geographic disparities in breastfeeding rates nationally.