First Nations Peoples' perceptions, knowledge and beliefs regarding stillbirth prevention and bereavement practices: A mixed methods systematic review.

BACKGROUND: First Nations Peoples endure disproportionate rates of stillbirth compared with non-First Nations Peoples. Previous interventions have aimed at reducing stillbirth in First Nations Peoples and providing better bereavement care without necessarily understanding the perceptions, knowledge and beliefs that could influence the design of the intervention and implementation. AIM: The aim of this review was to understand the perceptions, knowledge and beliefs about stillbirth prevention and bereavement of First Nations Peoples from the US, Canada, Aotearoa/New Zealand, and Australia. METHODS: This review was conducted in accordance with the JBI methodology for a convergent integrated mixed method systematic review. This review was overseen by an advisory board of Aboriginal Elders, researchers, and clinicians. A search of eight databases (PubMed, MEDLINE, PsycInfo, CINAHL, Embase, Emcare, Dissertations and Theses and Indigenous Health InfoNet) and grey literature was conducted. All studies were screened, extracted, and appraised for quality by two reviewers and results were categorised, and narratively summarised. RESULTS: Ten studies were included within this review. Their findings were summarised into four categories: safeguarding baby, traditional practices of birthing and grieving, bereavement photography and post-mortem examination. The results indicate a diversity of perceptions, knowledge and beliefs primarily around smoking cessation and bereavement practices after stillbirth. However, there was a paucity of research available. CONCLUSIONS: Further research is needed to understand the perceptions, knowledge and beliefs about stillbirth among First Nations Peoples. Without research within this area, interventions to prevent stillbirth and support bereaved parents and their communities after stillbirth may face barriers to implementation.

Nonchromosomal birth defects and risk of childhood acute leukemia: An assessment in 15 000 leukemia cases and 46 000 controls from the Childhood Cancer and Leukemia International Consortium.

Although recent studies have demonstrated associations between nonchromosomal birth defects and several pediatric cancers, less is known about their role on childhood leukemia susceptibility. Using data from the Childhood Cancer and Leukemia International Consortium, we evaluated associations between nonchromosomal birth defects and childhood leukemia. Pooling consortium data from 18 questionnaire-based and three registry-based case-control studies across 13 countries, we used multivariable logistic regression models to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for the association between a spectrum of birth defects and leukemia. Our analyses included acute lymphoblastic leukemia (ALL, n = 13 115) and acute myeloid leukemia (AML, n = 2120) cases, along with 46 172 controls. We used the false discovery rate to account for multiple comparisons. In the questionnaire-based studies, the prevalence of birth defects was 5% among cases vs 4% in controls, whereas, in the registry-based studies, the prevalence was 11% among cases vs 7% in controls. In pooled adjusted analyses, there were several notable associations, including (1) digestive system defects and ALL (OR = 2.70, 95% CI: 1.46-4.98); (2) congenital anomalies of the heart and circulatory system and AML (OR = 2.86, 95% CI: 1.81-4.52) and (3) nervous system defects and AML (OR = 4.23, 95% CI: 1.50-11.89). Effect sizes were generally larger in registry-based studies. Overall, our results could point to novel genetic and environmental factors associated with birth defects that could also increase leukemia susceptibility. Additionally, differences between questionnaire- and registry-based studies point to the importance of complementary sources of birth defect phenotype data when exploring these associations.

Infant feeding practices and childhood acute leukemia: Findings from the Childhood Cancer & Leukemia International Consortium.

Increasing evidence suggests that breastfeeding may protect from childhood acute lymphoblastic leukemia (ALL) and acute myeloid leukemia (AML). However, most studies have limited their analyses to any breastfeeding, and only a few data have examined exclusive breastfeeding, or other exposures such as formula milk. We performed pooled analyses and individual participant data metaanalyses of data from 16 studies (N = 17 189 controls; N = 10 782 ALL and N = 1690 AML cases) from the Childhood Leukemia International Consortium (CLIC) to characterize the associations of breastfeeding duration with ALL and AML, as well as exclusive breastfeeding duration and age at introduction to formula with ALL. In unconditional multivariable logistic regression analyses of pooled data, we observed decreased odds of ALL among children breastfed 4 to 6 months (0.88, 95% CI 0.81-0.96) or 7 to 12 months (OR 0.85, 0.79-0.92). We observed a similar inverse association between breastfeeding ≥4 months and AML (0.82, 95% CI 0.71-0.95). Odds of ALL were reduced among children exclusively breastfed 4 to 6 months (OR 0.73, 95% CI 0.63-0.85) or 7 to 12 months (OR 0.70, 95% CI 0.53-0.92). Random effects metaanalyses produced similar estimates, and findings were unchanged in sensitivity analyses adjusted for race/ethnicity or mode of delivery, restricted to children diagnosed ≥1 year of age or diagnosed with B-ALL. Our pooled analyses indicate that longer breastfeeding is associated with decreased odds of ALL and AML. Few risk factors for ALL and AML have been described, therefore our findings highlight the need to promote breastfeeding for leukemia prevention.

Disparities in severe neonatal morbidity and mortality between Aboriginal and non-Aboriginal births in Western Australia: a decomposition analysis.

BACKGROUND: The health disadvantages faced by Australian Aboriginal peoples are evidenced in early life, although few studies have focused on the reasons for population-level inequalities in more severe adverse outcomes. This study aimed to examine the scale of disparity in severe neonatal morbidity (SNM) and mortality between Aboriginal and non-Aboriginal births and quantify the relative contributions of important maternal and infant factors. METHOD: A retrospective cohort study with singleton live births (≥32 weeks' gestation) was conducted using Western Australia linked whole population datasets, from 1999 to 2015. Aboriginal status was determined based on the mothers' self-reported ethnic origin. An Australian validated indicator was adapted to identify neonates with SNM. The Oaxaca-Blinder method was employed to calculate the contribution of each maternal and infant factor to the disparity in SNM and mortality. RESULTS: Analyses included 425 070 births, with 15 967 (3.8%) SNM and mortality cases. The disparity in SNM and mortality between Aboriginal and non-Aboriginal births was 2.9 percentage points (95% CI 2.6 to 3.2). About 71% of this gap was explained by differences in modelled factors including maternal area of residence (23.8%), gestational age (22.2%), maternal age (7.5%) and antenatal smoking (7.2%). CONCLUSIONS: There is a considerable disparity in SNM and mortality between Aboriginal and non-Aboriginal births in Western Australia with the majority of this related to differences in maternal sociodemographic factors, antenatal smoking and gestational age. Public health programmes targeting these factors may contribute to a reduction in early life health differentials and benefit Aboriginal population health through the life course.

Comparison of stillbirth trends over two decades in Wales, United Kingdom and Western Australia: An international retrospective cohort study.

BACKGROUND: Stillbirth is a critical public health issue worldwide. While the rates in high-income countries are relatively low, there are persistent between-country disparities. OBJECTIVES: To compare stillbirth rates and trends in Wales and the State of Western Australia (WA), Australia, and provide insights into any differences. METHODS: In this international retrospective cohort study, we pooled population-based data collections of all births ≥24 weeks' gestation (excluding terminations for congenital anomalies) between 1993 and 2015, divided into six time periods. The stillbirth rate per 1000 births was estimated for each cohort in each time period. Multivariable Poisson regression analyses, adjusted for appropriateness of growth, socio-economic status, maternal age, and multiple birth, were performed to evaluate the interaction between cohort and time period. Relative risk (RR) and 95% confidence interval (CI) for each time period and cohort were calculated. RESULTS: There were 767 731 births (3725 stillbirths) in Wales and 648 373 (2431 stillbirths) in WA. The overall stillbirth rate declined by 15.9% over the study period in Wales (from 5.3 in 1993-96 to 4.5 per 1000 births in 2013-15; Ptrend  < .01) but by 40.4% in WA (from 4.9 to 2.9 per 1000 births in WA; Ptrend  < .01). Using 1993-96 in WA as the reference group, the adjusted RRs for stillbirths at 37-38 weeks' gestation in the most recent study period (2013-15) were 0.85 (95% CI 0.64, 1.13) in Wales and 0.51 (95% CI 0.36, 0.73) in WA. CONCLUSIONS: The stillbirth rates between Wales and WA have widened in the last two decades (especially among late-term births), although the absolute rates for both are distinctly higher than the best-performing nations. While the differences may be partly explained by timing of birth and maternal life style behaviours such as smoking, it is important to identify and ameliorate the associated risk factors to support a reduction in preventable stillbirths.

Parental occupational exposure to pesticides and risk of childhood cancer in Switzerland: a census-based cohort study.

BACKGROUND: Pesticide exposure is a suspected risk factor for childhood cancer. We investigated the risk of developing childhood cancer in relation to parental occupational exposure to pesticides in Switzerland for the period 1990-2015. METHODS: From a nationwide census-based cohort study in Switzerland, we included children aged < 16 years at national censuses of 1990 and 2000 and followed them until 2015. We extracted parental occupations reported at the census closest to the birth year of the child and estimated exposure to pesticides using a job exposure matrix. Cox proportional hazards models, adjusted for potential confounders, were fitted for the following outcomes: any cancer, leukaemia, central nervous system tumours (CNST), lymphoma, non-CNS solid tumours. RESULTS: Analyses of maternal (paternal) exposure were based on approximately 15.9 (15.1) million-person years at risk and included 1891 (1808) cases of cancer, of which 532 (503) were leukaemia, 348 (337) lymphomas, 423 (399) CNST, and 588 (569) non-CNS solid tumours. The prevalence of high likelihood of exposure was 2.9% for mothers and 6.7% for fathers. No evidence of an association was found with maternal or paternal exposure for any of the outcomes, except for "non-CNS solid tumours" (High versus None; Father: adjusted HR [95%CI] =1.84 [1.31-2.58]; Mother: 1.79 [1.13-2.84]). No evidence of an association was found for main subtypes of leukaemia and lymphoma. A post-hoc analysis on frequent subtypes of "non-CNS solid tumours" showed positive associations with wide CIs for some cancers. CONCLUSION: Our study suggests an increased risk for solid tumours other than in the CNS among children whose parents were occupationally exposed to pesticides; however, the small numbers of cases limited a closer investigation of cancer subtypes. Better exposure assessment and pooled studies are needed to further explore a possible link between specific childhood cancers types and parental occupational exposure to pesticides.

Profile of severely growth-restricted births undelivered at 40 weeks in Western Australia.

PURPOSE: To investigate the proportion of severely growth-restricted singleton births < 3rd percentile (proxy for severe fetal growth restriction; FGR) undelivered at 40 weeks (FGR_40), and compare maternal characteristics and outcomes of FGR_40 births and FGR births at 37-39 weeks' (FGR_37-39) to those not born small-for-gestational-age at term (Not SGA_37+). METHODS: The annual rates of singleton FGR_40 births from 2006 to 2015 were calculated using data from linked Western Australian population health datasets. Using 2013-2015 data, maternal factors associated with FGR births were investigated using multinomial logistic regression to estimate odds ratios (OR) with 95% confidence intervals (CI) while relative risks (RR) of birth outcomes between each group were calculated using Poisson regression. Neonatal adverse outcomes were identified using a published composite indicator (diagnoses, procedures and other factors). RESULTS: The rate of singleton FGR_40 births decreased by 23.0% between 2006 and 2015. Factors strongly associated with FGR_40 and FGR_37-39 births compared to Not SGA_37+ births included the mother being primiparous (ORs 3.13: 95% CI 2.59-3.79; 1.69, 95% CI 1.47, 1.94, respectively) and ante-natal smoking (ORs 2.55, 95% CI 1.97, 3.32; 4.48, 95% CI 3.74, 5.36, respectively). FGR_40 and FGR_37-39 infants were more likely to have a neonatal adverse outcome (RRs 1.70, 95% CI 1.41, 2.06 and 2.46 95% CI 2.18, 2.46, respectively) compared to Not SGA 37+ infants. CONCLUSIONS: Higher levels of poor perinatal outcomes among FGR births highlight the importance of appropriate management including fetal growth monitoring. Regular population-level monitoring of FGR_40 rates may lead to reduced numbers of poor outcomes.

Family history of cancer and the risk of childhood brain tumors: a pooled analysis of the ESCALE and ESTELLE studies (SFCE).

PURPOSE: Although some specific genetic syndromes such as neurofibromatosis (NF) have been identified as risk factor of childhood brain tumors (CBT), the potential role of inherited susceptibility in CBT has yet to be elucidated. METHODS: To further investigate this, we conducted a pooled analysis of two nationwide case-control studies ESCALE and ESTELLE. The mothers of 509 CBT cases and 3,102 controls aged under 15 years who resided in France at diagnosis/interview, frequency-matched by age and gender, responded to a telephone interview conducted by trained interviewers. Pooled odds ratio (OR) and 95% confidence intervals (95% CI) were estimated using unconditional logistic regression. RESULTS: CBT was significantly associated with the family history of cancer in relatives (OR 1.2, 95% CI 1.0-1.5). The OR was slightly higher for maternal relatives than for paternal relatives, and when at least two relatives had a history of cancer. CBT was significantly associated with a family history of brain tumor (OR 2.1, 95% CI 1.3-3.7). This association seemed stronger for first-degree relatives (mother, father, and siblings), for whom, by contrast, no association was seen for cancers other than CBT. No specificity by CBT subtypes or by age of the children were found for any of these findings. CONCLUSION: Our findings support the hypothesis of a familial susceptibility of CBT, not due to being a known NF carrier.

Parental smoking, maternal alcohol consumption during pregnancy and the risk of neuroblastoma in children. A pooled analysis of the ESCALE and ESTELLE French studies.

Neuroblastoma (NB) is the most common extra-cranial tumour in children. Little is known about the aetiology of NB. The early age at onset and the embryonic nature suggest a role for perinatal exposures. We conducted a pooled analysis of two French national population-based case-control studies to explore whether there was an association between parental smoking and alcohol consumption and the risk of NB. The mothers of 357 NB cases and 1,783 controls from general population, frequency matched by age and sex, were interviewed on demographic, socioeconomic and perinatal characteristics, maternal reproductive story, and life-style and childhood environment. Unconditional logistic regression was used to estimate pooled odds ratios and 95% confidence intervals. A meta-analysis of our findings with those of previous studies was also conducted. Maternal smoking during pregnancy was slightly more often reported for the cases (24.1%) than for the controls (19.7%) (OR 1.3 [95% CI 0.9-1.7]; summary OR from meta-analysis 1.1 [95% CI 1.0-1.3]. Paternal smoking in the year before child's birth were not associated with NB as independent exposure (OR 1.1 [95% CI 0.9-1.4] but the association was stronger when both parents reported having smoked during pregnancy (OR 1.5 [95% CI 1.1-2.1]. No association was observed with maternal alcohol intake during pregnancy (OR 1.0 [95% CI 0.8-1.4], summary OR from meta-analysis 1.0 [95% CI 0.9-1.2]. Our findings provide some evidence of an association between maternal smoking during pregnancy and NB and add another reason to recommend that women refrain from smoking during pregnancy.

Living on a farm, contact with farm animals and pets, and childhood acute lymphoblastic leukemia: pooled and meta-analyses from the Childhood Leukemia International Consortium.

The associations between childhood acute lymphoblastic leukemia (ALL) and several factors related to early stimulation of the immune system, that is, farm residence and regular contacts with farm animals (livestock, poultry) or pets in early childhood, were investigated using data from 13 case-control studies participating in the Childhood Leukemia International Consortium. The sample included 7847 ALL cases and 11,667 controls aged 1-14 years. In all studies, the data were obtained from case and control parents using standardized questionnaires. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated by unconditional logistic regression adjusted for age, sex, study, maternal education, and maternal age. Contact with livestock in the first year of life was inversely associated with ALL (OR = 0.65, 95% CI: 0.50, 0.85). Inverse associations were also observed for contact with dogs (OR = 0.92, 95% CI: 0.86, 0.99) and cats (OR = 0.87, 95% CI: 0.80, 0.94) in the first year of life. There was no evidence of a significant association with farm residence in the first year of life. The findings of these large pooled and meta-analyses add additional evidence to the hypothesis that regular contact with animals in early childhood is inversely associated with childhood ALL occurrence which is consistent with Greaves' delayed infection hypothesis.

Maternal consumption of coffee and tea during pregnancy and risk of childhood ALL: a pooled analysis from the childhood Leukemia International Consortium.

PURPOSE: The early onset of childhood acute lymphoblastic leukemia (ALL) suggests that critical exposures occurring during pregnancy may increase risk. We investigated the effects of maternal coffee and tea consumption during pregnancy on ALL risk by pooling data from eight case-control studies participating in the Childhood Leukemia International Consortium. METHOD: Data on maternal coffee intake were available for 2,552 cases and 4,876 controls, and data on tea intake were available for 2,982 cases and 5,367 controls. Coffee and tea intake was categorized into 0, > 0-1, > 1-2, and > 2 cups/day, and covariates were combined and harmonized. Data on genetic variants in NAT2, CYP1A1, and NQO1 were also available in a subset. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using unconditional logistic regression, and linear trends across categories were assessed. RESULTS: No association was seen with 'any' maternal coffee consumption during pregnancy, but there was evidence of a positive exposure-response; the pooled OR for > 2 cups/day versus none was 1.27 (95% CI 1.09-1.43), p trend = 0.005. No associations were observed with tea consumption. No interactions were seen between coffee or tea intake and age, maternal smoking or genotype, and there was little or no evidence that associations with coffee or tea differed among cases with and without chromosomal translocations. CONCLUSIONS: Despite some limitations, our findings suggest that high coffee intake during pregnancy may increase risk of childhood ALL. Thus, current advice to limit caffeine intake during pregnancy to reduce risk of preterm birth may have additional benefits.

Maternal residential pesticide use during pregnancy and risk of malignant childhood brain tumors: A pooled analysis of the ESCALE and ESTELLE studies (SFCE).

Some previous epidemiological studies have suggested that pesticide exposure during pregnancy may have a possible role in the development of childhood brain tumors (CBT). We pooled data from two French national population-based, case-control studies to investigate the association between maternal residential use of pesticides during pregnancy and the risk of CBT. The mothers of 437 CBT cases and 3,102 controls aged under 15 years who resided in France at diagnosis/interview, frequency-matched by age and gender, answered a structured telephone interview conducted by trained interviewers. Unconditional logistic regression was used to estimate pooled odds ratio (OR) and 95% confidence intervals (95% CI). CBT was significantly associated with the maternal home use of pesticides during pregnancy (OR 1.4, 95% CI 1.2-1.8) and, more specifically, with insecticide (OR 1.4, 1.2-1.8). We could not draw any conclusions about herbicides and/or fungicides because few women used them during pregnancy and most of these mothers also used insecticides. Although potential recall bias cannot be excluded, our findings of this pooled analysis support the hypothesis that residential maternal use of pesticides during pregnancy and particularly insecticides may increase the risk of CBT. Future investigations to verify these findings and to explore for CBT subtypes and dose-response are necessary to have a better understanding of the possible role of pesticides in etiology of CBT.

Childhood brain tumours, early infections and immune stimulation: A pooled analysis of the ESCALE and ESTELLE case-control studies (SFCE, France).

BACKGROUND: Few studies have investigated whether early infections and factors potentially related to early immune stimulation might be involved in the aetiology of childhood brain tumours (CBT). In this study, we investigated the associations between CBT with early day-care attendance, history of early common infections, atopic conditions (asthma/wheezing, eczema, allergic rhinitis), early farm residence/visits and contact with animals. METHODS: We pooled data from two nationwide French case-control studies, the ESCALE and ESTELLE studies. Children with a CBT diagnosed between 1 and 14 years of age were identified directly from the French National Registry of Childhood Cancers, while population controls were recruited from telephone subscribers. Odds-ratios (OR) and 95% confidence intervals (CI) were estimated using logistic regression adjusted for potential confounders. RESULTS: The analyses included 469 cases and 2719 controls. We found no association between attending a day-care centre (OR: 0.9, 95%CI: 0.7-1.2) or having had repeated common infections (OR: 0.9, 95%CI: 0.7-1.2) in the first year of life and the risk of CBT. There was also no association with a history of asthma/wheezing (OR: 0.8, 95%CI: 0.56-1.1). Farm visits (OR: 0.6, 95%CI: 0.5-0.8) as well as contact with pets (OR: 0.8, 95%CI: 0.6-1.0) in the first year of life were inversely associated with CBT. CONCLUSIONS: Our findings suggest a protective effect of early farm visits and contact with pets, but not with other markers of early immune stimulation. This might be related to immune stimulation but needs further investigation.

Maternal use of household pesticides during pregnancy and risk of neuroblastoma in offspring. A pooled analysis of the ESTELLE and ESCALE French studies (SFCE).

PURPOSE: Neuroblastoma (NB) is an embryonic tumor that occurs almost exclusively in infancy and early childhood. While considerable evidence suggests that it may be initiated during embryonic development, the etiology of NB is still unknown. The aim of this study was to explore whether there is an association between maternal use of household pesticides during pregnancy and the risk of NB in the offspring. METHODS: We conducted a pooled analysis of two French national-based case-control studies. The mothers of 357 NB cases and 1,783 controls younger than 6 years, frequency-matched by age and gender, responded to a telephone interview that focused on sociodemographic and perinatal characteristics, childhood environment, and life-style. Unconditional logistic regression was used to estimate pooled odds ratios and 95% confidence intervals. RESULTS: After controlling for matching variables, study of origin, and potential confounders, the maternal use of any type of pesticide during pregnancy was associated with NB (OR 1.5 [95% CI 1.2-1.9]). The most commonly used type of pesticides were insecticides and there was a positive association with their use alone (OR 1.4 [95% CI 1.1-1.9]) or with other pesticides (OR 2.0 [95% CI 1.1-3.4]). CONCLUSIONS: Although there is the potential for recall bias due to the study design, our findings add to the evidence of an association between the household use of pesticides and NB. Until a better study design can be found, our findings add yet another reason why to advise pregnant women to limit pesticide exposure during the periconceptional period.

Parental smoking, maternal alcohol, coffee and tea consumption and the risk of childhood brain tumours: the ESTELLE and ESCALE studies (SFCE, France).

PURPOSE: To investigate whether parental smoking around the time of pregnancy or maternal consumption of beverages (alcohol, coffee, or tea) during pregnancy were associated with the risk of CBT. METHODS: We pooled data from two French national population-based case-control studies with similar designs conducted in 2003-2004 and 2010-2011. The mothers of 510 CBT cases (directly recruited from the national childhood cancer register) and 3,102 controls aged under 15 years, frequency matched by age and gender, were interviewed through telephone, which included questions about prenatal parental smoking and maternal consumption of alcohol, coffee and tea. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression, adjusted for age, sex and study of origin. RESULTS: No association was seen between CBT and the mother smoking or drinking alcohol, coffee, or tea during the index pregnancy. The OR between CBT and paternal smoking in the year before birth (as reported by the mother) was 1.25 (95% CI 1.03, 1.52) with an OR of 1.09 (0.99, 1.19) for every 10 cigarettes per day (CPD) smoked. The association between paternal smoking and CBT appeared to be stronger in children diagnosed before the age of five years (OR 1.52, 95% CI 1.14, 2.02) and for astrocytoma (OR 1.86, 95% CI 1.26, 2.74). CONCLUSION: We found some evidence of a weak association between paternal smoking in the year before the child's birth and CBT, especially astrocytomas. These findings need to be replicated in other samples, using similar classifications of tumour subtypes.

Factors related to pregnancy and birth and the risk of childhood brain tumours: The ESTELLE and ESCALE studies (SFCE, France).

Little is known of the causes of childhood brain tumors (CBT). The aims of this study were to investigate whether extremes of birth weight were associated with increased risk of CBT and whether maternal preconceptional folic acid supplementation or breastfeeding reduced the risk. In addition, other maternal characteristics and birth related factors were also investigated. We pooled data from two French national population-based case-control studies with similar designs conducted in 2003-2004 and 2010-2011. The mothers of 510 CBT cases (directly recruited from the national childhood cancer register) and 3,102 controls aged under 15 years, frequency matched by age and gender did a telephone interview, which focussed on demographic and perinatal characteristics, and maternal life style habits and reproductive history. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using unconditional logistic regression, adjusted for age, sex, study of origin and relevant confounders. No association was found between CBT and birth weight or fetal growth. The use of preconceptional folic acid supplementation was rare (5.3% in cases and 7.8% in controls) and the OR was 0.8 (95% CI 0.5, 1.4). There was no association with breastfeeding, even prolonged (six months or more; OR 1.0, 95% CI 0.8, 1.4). Neither was there any association between CBT and other investigated factors (maternal body mass index, gestational weight gain, congenital abnormality, maternal reproductive history or use of fertility treatments. Although large, this study was underpowered for subtype analyses. Pooling data with other population-based studies may provide further insight into findings by CBT subtypes.

Risk of Central Nervous System Tumors in Children Related to Parental Occupational Pesticide Exposures in three European Case-Control Studies.

OBJECTIVE: The aim of this study was to assess the risk of childhood central nervous system (CNS) tumors associated with parental occupational pesticide exposure. METHODS: We pooled three population-based case-control studies from France, Germany, and the United Kingdom. Cases were children below 15 years of age with CNS tumors; controls were matched by gender and age. A general population job-exposure matrix assessed parental occupational pesticide exposure. Logistic regressions estimated odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: The study included 1361 cases and 5498 controls. Prevalence of maternal occupational pesticide exposure during pregnancy was low and no association with childhood CNS tumors was detected (OR 0.76, 95% CI: 0.41 to 1.41). Around conception, OR for childhood CNS tumors associated with paternal occupational pesticide exposure was 0.71 (95% CI: 0.53 to 0.95). CONCLUSION: Our results do not suggest a role of parental occupational pesticide exposure in the etiology of childhood CNS tumors.

Risk of neuroblastoma, birth-related characteristics, congenital malformations and perinatal exposures: A pooled analysis of the ESCALE and ESTELLE French studies (SFCE).

Neuroblastoma (NB), an embryonic tumour arising from neural crest cells, is the most common malignancy among infants. The aetiology of NB is largely unknown. We conducted a pooled analysis to explore whether there is an association between NB and preconception and perinatal factors using data from two French national population-based case-control studies. The mothers of 357 NB cases and 1783 controls younger than 6 years, frequency-matched by age and gender, responded to a telephone interview that focused on demographic, socioeconomic and perinatal characteristics, childhood environment, life-style and maternal reproductive history. Unconditional logistic regression was used to estimate pooled odds ratios and 95% confidence intervals. After controlling for matching variables, study of origin and potential confounders, being born either small (OR 1.4 95% CI 1.0-2.0) or large (OR 1.5 95% CI 1.1-2.2) for gestational age and, among children younger than 18 months, having congenital malformations (OR 3.6 95% CI 1.3-8.9), were significantly associated with NB. Inverse associations were observed with breastfeeding (OR 0.7 95% CI 0.5-1.0) and maternal use of any supplements containing folic acid, vitamins or minerals (OR 0.5 95% CI 0.3-0.9) during the preconception period. Our findings reinforce the hypothesis that fetal growth anomalies and congenital malformations may be associated with an increased risk of NB. Further investigations are needed in order to clarify the role of folic acid supplementation and breastfeeding, given their potential importance in NB prevention.