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Background: Concern over the health effects of BPA, particularly for the developing fetus, has led to an increasing use of bisphenol analogues in industrial and consumer products, which may be as hormonally active as BPA. Biomonitoring data for many bisphenol analogues, especially in pregnant populations, are limited., Methods: We measured concentrations of 14 bisphenol analogues in 1 st trimester urine samples (n = 1851) from the Maternal-Infant Research on Environmental Chemicals (MIREC) Canadian pregnancy cohort (2008-2011). We examined patterns of exposure according to sociodemographic and sampling characteristics as well as occupation and frequency of consumption of canned fish within the previous 3 months., Results: BPA was detected in 89% of participants with a specific gravity standardized geometric mean concentration of 0.990 μg/L. Biphenol 4,4' (BP 4,4'), 4,4'-dihydroxydiphenyl ether (DHDPE), and bisphenol E (BPE) were detected in >97% of participants. Bisphenol F (BPF) and bisphenol S (BPS) were detected in >60% of participants. Specific gravity standardized geometric mean concentrations of these 5 compounds ranged from 0.024 to 0.564 μg/L. Nine bisphenol analogues were detected in <9% of participants. Concentrations of BP 4,4', DHDPE, and BPE were higher in younger women and those with higher pre-pregnancy BMI, lower household income, lower education, and among smokers. We found a similar pattern of differences in BPF for age, education, and smoking status while BPS similarly differed across categories of pre-pregnancy BMI. Participants who were unemployed or working in the service industry had higher molar sum of 7 bisphenol analogues than those working in healthcare, education, or an office setting. Canned fish consumption was not related to bisphenol analogue concentrations., Conclusion: BP 4,4', DHDPE, BPE, BPF, and BPS were highly detected in 1 st trimester urine samples in this large pan-Canadian pregnancy cohort. This suggests widespread exposure to these analogues around 2008-2011 and warrants further investigation into associations with health outcomes., (Copyright © 2023. Published by Elsevier GmbH.)

Background: Glyphosate is the most widely applied herbicide in agriculture. Glufosinate is a broad spectrum herbicide used to manage glyphosate-resistant weeds. Despite the widespread use of these herbicides, biomonitoring data - which inform risk assessment and management - are sparse., Objectives: To identify determinants of urinary concentrations of these herbicides and their metabolites in pregnancy., Methods: We measured urinary concentrations of glyphosate, glufosinate, and their primary metabolites aminomethylphosphonic acid (AMPA) and 3-methylphosphinicopropionic acid (3-MPPA) in a single spot urine specimen collected during the first trimester of pregnancy from the Maternal-Infant Research on Environmental Chemicals (MIREC) study. MIREC recruited about 2000 pregnant women from 10 Canadian cities between 2008 and 2011. We used UItra-Performance Liquid Chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) with sensitive limits of detection to quantify analyte concentrations. We examined urinary concentrations according to maternal sociodemographics, sample collection characteristics, reported pesticide use, and consumption of fruits, vegetables, legumes, and grain products. We used ANOVA models with specific gravity-standardized chemical concentrations as the dependent variable to determine associations with maternal and sample determinants., Results: Among women with biobanked urine samples (n = 1829-1854), 74% and 72% had detectable concentrations of glyphosate and AMPA, respectively. In contrast, one and six percent of women had detectable concentrations of glufosinate and 3-MPPA, respectively. The specific gravity-standardized geometric mean (95% CI) concentrations of glyphosate and AMPA were 0.112 (0.099-0.127) μg/L and 0.159 (0.147-0.172) μg/L, respectively. We observed a dose-response relationship between consumption of whole grain bread and higher urinary glyphosate concentrations. Season of urine collection and self-reported pesticide use were not associated with increased concentrations of any analyte., Conclusions: We detected glyphosate and AMPA in the majority of pregnant women from this predominantly urban Canadian cohort. Diet was a probable route of exposure., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests:Warren G. Foster reports a relationship with Hollingsworth LLC that includes: paid expert testimony., (Crown Copyright © 2022. Published by Elsevier Inc. All rights reserved.)

Objective: To comprehensively describe current preimplantation genetic testing for aneuploidy (PGT-A) practices and management of non-euploid embryos in Canada., Methods: This was a cross-sectional study utilizing an online survey distributed by email to all medical directors of fertility clinics with independent in vitro fertilization (IVF) embryology laboratories. The survey was designed to determine practice patterns regarding PGT-A usage; PGT-A reference laboratory, platform, and thresholds for classifying embryos; and management of embryos classified as mosaic, inconclusive, or aneuploid., Results: Twenty-five medical directors (69%) participated in the survey. The majority of clinics (91%) offered PGT-A screening, with 45% of clinics offering PGT-A as routine screening. The majority of clinics (90%) that offered PGT-A received mosaicism data; 61% of these clinics had transferred mosaic embryos, and 94% would transfer mosaic embryos. Clinics that performed ≥1000 IVF cycles annually were more likely to have transferred mosaic embryos (100% vs. 45.5%; P = 0.043). The mean percentage of IVF cycles using PGT-A was lower in clinics that had transferred mosaic embryos (12.3% vs. 30.4%; P = 0.033). Only 1 clinic had transferred an aneuploid embryo, but 2 other clinics would consider this option. The majority of clinics (61%) that receive mosaicism data would recommend noninvasive prenatal testing (NIPT) following mosaic embryo transfer, with 22% of clinics indicating that this would be the only genetic test offered., Conclusion: We report significant practice variation in PGT-A and management of non-euploid embryos across Canada and highlight areas where consensus should be encouraged., (Copyright © 2022 The Society of Obstetricians and Gynaecologists of Canada/La Société des obstétriciens et gynécologues du Canada. Published by Elsevier Inc. All rights reserved.)

Context: Fetal overgrowth "programs" an elevated risk of obesity and type 2 diabetes in adulthood. Plausibly, adipokines may be involved in programming metabolic health., Objective: This work aimed to evaluate whether large-for-gestational-age (LGA), an indicator of fetal overgrowth, is associated with altered circulating leptin and adiponectin levels in infancy, and assess the determinants., Methods: In the Canadian 3D birth cohort, we studied 70 LGA (birth weight > 90th percentile) and 140 optimal-for-gestational-age (OGA, 25th-75th percentiles) infants matched by maternal ethnicity, smoking, and gestational age at delivery. The primary outcomes were fasting leptin, and total and high-molecular-weight (HMW) adiponectin concentrations at age 2 years., Results: LGA infants had higher body mass index (BMI) than OGA infants. However, there were no significant differences in leptin, and total and HMW adiponectin concentrations. Leptin concentrations were positively associated with female sex, weight (z score) gain 0 to 24 months, current BMI, and the sum of triceps and subscapular skinfold thickness, and negatively associated with maternal age and White ethnicity. Female sex was associated with lower total and HMW adiponectin concentrations. Weight (z score) gain 0 to 24 months and current BMI were positively correlated with total and HMW adiponectin concentrations in LGA infants only., Conclusion: This study is the first to demonstrate that LGA does not matter for circulating leptin and adiponectin concentrations in infancy, and there may be LGA-specific positive associations between weight gain or current BMI and adiponectin concentrations in infancy, suggesting dysfunction in establishing the adiposity-adiponectin negative feedback loop in LGA individuals., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Exposure to oil sands process-affected water (OSPW), a by-product of Canadian oil sands mining operations, can cause both acute and chronic adverse effects in aquatic life. Ozonation effectively degrades naphthenic acids in OSPW, mitigating some of the toxicological effects of exposure. In this study we examined the effect of developmental exposure to raw and ozonated OSPW had on the breeding success, prey capture, and alarm cue response in fish months/years after exposure and the transgenerational effect exposure had on gene expression, global DNA methylation, and larval basal activity. Exposure to raw and ozonated OSPW had no effect on breeding success, and global DNA methylation. Exposure altered the expression of vtg and nkx2.5 in the unexposed F1 generation. Exposure to both raw and ozonated OSPW had a transgenerational impact on larval activity levels, anxiety behaviors, and maximum swim speed compared to the control population. Prey capture success was unaffected, however, the variability in the behavioral responses to the introduction of prey was decreased. Fish developmentally exposed to either treatment were less active before exposure and did not have an anxiety response to the alarm cue hypoxanthine-3-n-oxide. Though ozonation was able to mitigate some of the effects of OSPW exposure, further studies are needed to understand the transgenerational effects and the implications of exposure on complex fish behaviors., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This article investigates the role of proxy data in dealing with the common problem of missing data in clinical trials using repeated measures designs. In an effort to avoid the missing data situation, some proxy information can be gathered. The question is how to treat proxy information, that is, is it always better to utilize proxy information when there are missing data? A model for repeated measures data with missing values is considered and a strategy for utilizing proxy information is developed. Then, simulations are used to compare the power of a test using proxy to simply utilizing all available data. It is concluded that using proxy information can be a useful alternative when such information is available. The implications for various clinical designs are also considered and a data collection strategy for efficiently estimating parameters is suggested.