Use of Chemical Hair Straighteners and Fecundability in a North American Preconception Cohort.

Chemical hair straighteners ("relaxers") are used by millions of North Americans, particularly women of color. Hair relaxers may contain endocrine-disrupting compounds, which can harm fertility. We evaluated the association between hair relaxer use and fecundability among 11,274 participants from Pregnancy Study Online (PRESTO), a North American preconception cohort study. During 2014-2022, participants completed a baseline questionnaire in which they reported their history of relaxer use and completed follow-up questionnaires every 8 weeks for 12 months or until pregnancy, whichever came first. We used multivariable-adjusted proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% confidence intervals (CIs). Relative to never use, fecundability was lower among current (FR = 0.81, 95% CI: 0.64, 1.03) and former (FR = 0.89, 95% CI: 0.81, 0.98) users of hair relaxers. FRs for first use of hair relaxers at ages <10, 10-19, and ≥20 years were 0.73 (95% CI: 0.55, 0.96), 0.93 (95% CI: 0.83, 1.04), and 0.85 (95% CI: 0.74, 0.98), respectively. Fecundability was lowest among those with longer durations of use (≥10 years vs. never: FR = 0.71, 95% CI: 0.54, 0.91) and more frequent use (≥5 times/year vs. never: FR = 0.82, 95% CI: 0.60, 1.11), but associations were nonmonotonic. In this preconception cohort study, use of chemical hair straighteners was associated with slightly reduced fecundability.

Association of male fatty acid intake with fecundability among couples planning pregnancy.

STUDY QUESTION: To what extent is male fatty acid intake associated with fecundability among couples planning pregnancy? SUMMARY ANSWER: We observed weak positive associations of male dietary intakes of total and saturated fatty acids with fecundability; no other fatty acid subtypes were appreciably associated with fecundability. WHAT IS KNOWN ALREADY: Male fatty acid intake has been associated with semen quality in previous studies. However, little is known about the extent to which male fatty acid intake is associated with fecundability among couples attempting spontaneous conception. STUDY DESIGN, SIZE, DURATION: We conducted an internet-based preconception prospective cohort study of 697 couples who enrolled during 2015-2022. During 12 cycles of observation, 53 couples (7.6%) were lost to follow-up. PARTICIPANTS/MATERIALS, SETTING, METHODS: Participants were residents of the USA or Canada, aged 21-45 years, and not using fertility treatment at enrollment. At baseline, male participants completed a food frequency questionnaire from which we estimated intakes of total fat and fatty acid subtypes. We ascertained time to pregnancy using questionnaires completed every 8 weeks by female participants until conception or up to 12 months. We used proportional probabilities regression models to estimate fecundability ratios (FRs) and 95% CIs for the associations of fat intakes with fecundability, adjusting for male and female partner characteristics. We used the multivariate nutrient density method to account for energy intake, allowing for interpretation of results as fat intake replacing carbohydrate intake. We conducted several sensitivity analyses to assess the potential for confounding, selection bias, and reverse causation. MAIN RESULTS AND THE ROLE OF CHANCE: Among 697 couples, we observed 465 pregnancies during 2970 menstrual cycles of follow-up. The cumulative incidence of pregnancy during 12 cycles of follow-up after accounting for censoring was 76%. Intakes of total and saturated fatty acids were weakly, positively associated with fecundability. Fully adjusted FRs for quartiles of total fat intake were 1.32 (95% CI 1.01-1.71), 1.16 (95% CI 0.88-1.51), and 1.43 (95% CI 1.09-1.88) for the second, third, and fourth vs the first quartile, respectively. Fully adjusted FRs for saturated fatty acid intake were 1.21 (95% CI 0.94-1.55), 1.16 (95% CI 0.89-1.51), and 1.23 (95% CI 0.94-1.62) for the second, third, and fourth vs the first quartile, respectively. Intakes of monounsaturated, polyunsaturated, trans-, omega-3, and omega-6 fatty acids were not strongly associated with fecundability. Results were similar after adjustment for the female partner's intakes of trans- and omega-3 fats. LIMITATIONS, REASONS FOR CAUTION: Dietary intakes estimated from the food frequency questionnaire may be subject to non-differential misclassification, which is expected to bias results toward the null in the extreme categories when exposures are modeled as quartiles. There may be residual confounding by unmeasured dietary, lifestyle, or environmental factors. Sample size was limited, especially in subgroup analyses. WIDER IMPLICATIONS OF THE FINDINGS: Our results do not support a strong causal effect of male fatty acid intakes on fecundability among couples attempting to conceive spontaneously. The weak positive associations we observed between male dietary fat intakes and fecundability may reflect a combination of causal associations, measurement error, chance, and residual confounding. STUDY FUNDING/COMPETING INTEREST(S): The study was funded by the National Institutes of Health, grant numbers R01HD086742 and R01HD105863. In the last 3 years, PRESTO has received in-kind donations from Swiss Precision Diagnostics (home pregnancy tests) and Kindara.com (fertility app). L.A.W. is a consultant for AbbVie, Inc. M.L.E. is an advisor to Sandstone, Ro, Underdog, Dadi, Hannah, Doveras, and VSeat. The other authors have no competing interests to report. TRIAL REGISTRATION NUMBER: N/A.

A prospective ultrasound study of cigarette smoking and uterine leiomyomata incidence and growth.

BACKGROUND: Uterine leiomyomata (fibroids) are common, benign neoplasms that contribute substantially to gynecologic morbidity. Some existing epidemiologic studies indicate that cigarette smoking is associated with lower uterine leiomyomata risk. However, no prospective studies have systematically screened an entire study population for uterine leiomyomata using transvaginal ultrasound or evaluated the association between cigarette smoking and uterine leiomyomata growth. OBJECTIVE: This study aimed to examine the association between cigarette smoking and uterine leiomyomata incidence and growth in a prospective ultrasound study. STUDY DESIGN: We enrolled 1693 residents from the Detroit metropolitan area into the Study of Environment, Lifestyle, and Fibroids during 2010 to 2012. Eligible participants were aged 23 to 34 years, had an intact uterus but no previous diagnosis of uterine leiomyomata, and self-identified as Black or African American. We invited participants to complete a baseline visit and 4 follow-up visits over approximately 10 years. At each visit, we used transvaginal ultrasound to assess uterine leiomyomata incidence and growth. Participants provided extensive self-reported data throughout follow-up including exposures to active and passive cigarette smoking in adulthood. We excluded participants who did not return for any follow-up visits (n=76; 4%). We fit Cox proportional hazards regression models to estimate hazard ratios and 95% confidence intervals for the association between time-varying smoking history and incidence rates of uterine leiomyomata. We fit linear mixed models to estimate the percentage difference and 95% confidence intervals for the association between smoking history and uterine leiomyomata growth. We adjusted for sociodemographic, lifestyle, and reproductive factors. We interpreted our results based on magnitude and precision rather than binary significance testing. RESULTS: Among 1252 participants without ultrasound evidence of uterine leiomyomata at baseline, uterine leiomyomata were detected in 394 participants (31%) during follow-up. Current cigarette smoking was associated with a lower uterine leiomyomata incidence rate (hazard ratio, 0.67; 95% confidence interval, 0.49-0.92). Associations were stronger among participants who had smoked for longer durations (≥15 years vs never: hazard ratio, 0.49; 95% confidence interval, 0.25-0.95). The hazard ratio for former smokers was 0.78 (95% confidence interval, 0.50-1.20). Among never smokers, the hazard ratio for current passive smoke exposure was 0.84 (95% confidence interval, 0.65-1.07). Uterine leiomyomata growth was not appreciably associated with current (percent difference, -3%; 95% confidence interval, -13% to 8%) or former (percent difference, -9%; 95% confidence interval, -22% to 6%) smoking. CONCLUSION: We provide evidence from a prospective ultrasound study that cigarette smoking is associated with lower uterine leiomyomata incidence.

Case-control study of exclusive breast feeding and severe bronchiolitis in the United States.

BACKGROUND: Bronchiolitis is a major cause of infant illness, with few known modifiable risk factors. Breast feeding may reduce risk of severe bronchiolitis, but the association of exclusive vs. partial breast feeding with severe bronchiolitis is unclear. OBJECTIVE: To estimate the association of exclusive vs. partial breast feeding during ages 0-2.9 months with bronchiolitis hospitalisation during infancy. METHODS: We conducted a case-control study as a secondary analysis of two prospective US cohorts in the Multicenter Airway Research Collaboration. Cases were enrolled in a 17-centre study of infants hospitalised for bronchiolitis during 2011-2014 (n = 921). Controls were enrolled in a five-centre study of healthy infants during 2013-2014 and 2017 (n = 719). Breast feeding history during ages 0-2.9 months was collected by parent interview. Among breastfed infants, the association of exclusive vs. partial breast feeding with odds of bronchiolitis hospitalisation was estimated using a multivariable logistic regression model adjusted for demographic variables, parental asthma history, and early-life exposures. As a secondary analysis, we estimated the associations of exclusive, predominant, and occasional breast feeding vs. no breast feeding with the odds of bronchiolitis hospitalisation. RESULTS: Among 1640 infants, the prevalence of exclusive breast feeding was 187/921 (20.3%) among cases and 275/719 (38.3%) among controls. Exclusive vs. partial breast feeding was associated with 48% reduced odds of bronchiolitis hospitalisation (adjusted odds ratio [OR] 0.52, 95% confidence interval [CI] 0.39, 0.69). In the secondary analysis, exclusive vs. no breast feeding was associated with 58% reduced odds of bronchiolitis hospitalisation (OR 0.42, 95% CI 0.23, 0.77), whereas predominant breast feeding (OR 0.77, 95% CI 0.37, 1.57) and occasional breast feeding (OR 0.98, 95% CI 0.57, 1.69) were not associated with meaningfully reduced odds of bronchiolitis hospitalisation. CONCLUSION: Exclusive breast feeding had a strong protective association against bronchiolitis hospitalisation.

Experiences of racism and perinatal depression: Findings from the pregnancy risk assessment monitoring system, 2018.

AIM: To estimate the association between feeling upset by experiences of racism and self-reported depression during pregnancy among non-Hispanic Black women using a large population-based sample from the United States. DESIGN: We conducted a secondary analysis of nationally representative cross-sectional survey data with retrospective measures. METHODS: Analysis of Phase 8 (2018) data from the Pregnancy Risk Assessment Monitoring System survey included 7328 non-Hispanic Black respondents with a recent live birth from 11 states and New York City. Multivariable logistic regression models were used to estimate the association between self-report of feeling upset due to experience of racism during the year prior to delivery and self-reported depression during pregnancy, controlling for potential confounders. RESULTS: The prevalence of feeling upset due to experiences of racism was 11.4% and the prevalence of depression during pregnancy was 11.4%. Respondents who reported feeling upset due to the experience of racism had over two-fold higher odds (OR 2.37, 95% CI 1.67, 3.37) of experiencing depression during pregnancy compared to respondents who did not report feeling upset due to the experience of racism, adjusted for maternal age, educational attainment, marital status, pre-pregnancy insurance type, region, and pre-pregnancy depression. CONCLUSION: Respondents who felt upset due to the experience of racism in the year prior to delivery experienced significantly higher odds of depression during pregnancy, and thus are at an increased risk for adverse maternal outcomes. IMPACT: Stress from racism and racial discrimination during the perinatal period may contribute to maternal morbidity, including perinatal depression, among Black women. NO PATIENT OR PUBLIC CONTRIBUTION: The data in this study were collected by the Centers for Disease Control and Prevention for the Pregnancy Risk Assessment Monitoring System. To our knowledge, the conduct of the study did not include patient or public contribution. Neither did the analysis, interpretation, nor manuscript preparation include patient or public contribution because we did not have funding to support the study or their involvement.

A Prospective Cohort Study of COVID-19 Vaccination, SARS-CoV-2 Infection, and Fertility.

Some reproductive-aged individuals remain unvaccinated against coronavirus disease 2019 (COVID-19) because of concerns about potential adverse effects on fertility. Using data from an internet-based preconception cohort study, we examined the associations of COVID-19 vaccination and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection with fertility among couples trying to conceive spontaneously. We enrolled 2,126 self-identified female participants aged 21-45 year residing in the United States or Canada during December 2020-September 2021 and followed them through November 2021. Participants completed questionnaires every 8 weeks on sociodemographics, lifestyle, medical factors, and partner information. We fit proportional probabilities regression models to estimate associations between self-reported COVID-19 vaccination and SARS-CoV-2 infection in both partners with fecundability (i.e., the per-cycle probability of conception), adjusting for potential confounders. COVID-19 vaccination was not appreciably associated with fecundability in either partner (female fecundability ratio (FR) = 1.08, 95% confidence interval (CI): 0.95, 1.23; male FR = 0.95, 95% CI: 0.83, 1.10). Female SARS-CoV-2 infection was not strongly associated with fecundability (FR = 1.07, 95% CI: 0.87, 1.31). Male infection was associated with a transient reduction in fecundability (for infection within 60 days, FR = 0.82, 95% CI: 0.47, 1.45; for infection after 60 days, FR = 1.16, 95% CI: 0.92, 1.47). These findings indicate that male SARS-CoV-2 infection may be associated with a short-term decline in fertility and that COVID-19 vaccination does not impair fertility in either partner.

Correlates of plasma concentrations of per- and poly-fluoroalkyl substances among reproductive-aged Black women.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are synthetic chemicals used in commercial and consumer goods. Black women are underrepresented in studies of PFAS exposure. METHODS: We performed a cross-sectional analysis of correlates of plasma PFAS concentrations among 1499 Black women aged 23-35 participating in the Study of Environment, Lifestyle, and Fibroids (SELF), a Detroit-based cohort study. At baseline (2010-2012), participants provided questionnaire data on socio-demographics; behaviors; diet; and menstrual, contraceptive, and reproductive histories. Using mass spectrometry in non-fasting plasma samples collected at enrollment, we quantified several PFAS, including perfluorohexane sulfonate (PFHxS), perfluorooctane sulfonate (PFOS), perfluorooctanoate (PFOA), perfluorononanoate (PFNA), perfluorodecanoate (PFDA), perfluoroundecanoate (PFUnDA), and 2-N-methyl-perfluorooctane sulfonamido acetate (MeFOSAA). We used linear regression to calculate percentage differences (%D) and 95 % confidence intervals (CIs) for associations between selected correlates and PFAS concentrations, adjusting for all other correlates. RESULTS: PFHxS, PFOS, PFOA, and PFNA were detected in ≥97 % of women; PFDA in 86 %; MeFOSAA in 70 %; and PFUnDA in 52 %. Age, income, education, and intakes of water, alcohol, and seafood were positively associated with several PFAS. Current smoking was positively associated with MeFOSAA. Body mass index was inversely associated with most PFAS, except PFHxS. Strong inverse associations (%D; 95 % CI) were observed between parity (≥3 vs. 0 births) and PFHxS (-34.7; -43.0, -25.1) and PFOA (-33.1; -39.2, -26.3); breastfeeding duration (≥6 months vs. nulliparous) and PFOA (-31.1; -37.8, -23.7), PFHxS (-24.2; -34.5, -12.3), and PFOS (-18.4; -28.3, -7.1); recent birth (<2 years ago vs. nulliparous) and PFOA (-33.1; -39.6, -25.8), PFHxS (-29.3; -39.0, -18.1), PFNA (-25.2; -32.7, -16.8), and PFOS (-18.3; -28.3, -6.9); and intensity of menstrual bleed (heavy vs. light) and PFHxS (-18.8; -28.3, -8.2), PFOS (-16.4; -24.9, -7.1), PFNA (-10.5; -17.8, -2.6), and PFOA (-10.0; -17.2, -2.1). Current use of depot medroxyprogesterone acetate (DMPA) was positively associated with PFOS (20.2; 1.4, 42.5), PFOA (16.2; 1.5, 33.0), and PFNA (15.3; 0.4, 32.4). CONCLUSIONS: Reproductive factors that influence PFAS elimination showed strong associations with several PFAS (reduced concentrations with parity, recent birth, lactation, heavy menstrual bleeding; increased concentrations with DMPA use).

Detection of Respiratory Syncytial Virus or Rhinovirus Weeks After Hospitalization for Bronchiolitis and the Risk of Recurrent Wheezing.

BACKGROUND: In severe bronchiolitis, it is unclear if delayed clearance or sequential infection of respiratory syncytial virus (RSV) or rhinovirus (RV) is associated with recurrent wheezing. METHODS: In a 17-center severe bronchiolitis cohort, we tested nasopharyngeal aspirates (NPA) upon hospitalization and 3 weeks later (clearance swab) for respiratory viruses using PCR. The same RSV subtype or RV genotype in NPA and clearance swab defined delayed clearance (DC); a new RSV subtype or RV genotype at clearance defined sequential infection (SI). Recurrent wheezing by age 3 years was defined per national asthma guidelines. RESULTS: Among 673 infants, RSV DC and RV DC were not associated with recurrent wheezing, and RSV SI was rare. The 128 infants with RV SI (19%) had nonsignificantly higher risk of recurrent wheezing (hazard ratio [HR], 1.31; 95% confidence interval [CI], .95-1.80; P = .10) versus infants without RV SI. Among infants with RV at hospitalization, those with RV SI had a higher risk of recurrent wheezing compared to children without RV SI (HR, 2.49; 95% CI, 1.22-5.06; P = .01). CONCLUSIONS: Among infants with severe bronchiolitis, those with RV at hospitalization followed by a new RV infection had the highest risk of recurrent wheezing.

Per- and polyfluoroalkyl substances (PFAS), perceived stress, and depressive symptoms in a prospective cohort study of black women.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals with neurotoxic properties. PFAS have been associated with depressive symptoms among women in some studies, but little research has evaluated the effects of PFAS mixtures. Further, no study has investigated interactions of PFAS-depression associations by perceived stress, which has been shown to modify the effects of PFAS on other health outcomes. OBJECTIVE: In a prospective cohort study of reproductive-aged Black women, we investigated associations between PFAS and depressive symptoms and the extent to which perceived stress modified these associations. METHODS: We analyzed data from 1499 participants (23-35 years) in the Study of Environment, Lifestyle, and Fibroids. We quantified concentrations of nine PFAS in baseline plasma samples using online solid-phase extraction-liquid chromatography-isotope dilution tandem mass spectrometry. Participants reported perceived stress via the Perceived Stress Scale (PSS-4; range = 0-16) at baseline and depressive symptoms via the Center for Epidemiologic Studies Depression Scale (CESD; range = 0-44) at the 20-month follow-up visit. We used Bayesian Kernel Machine Regression to estimate associations between PFAS concentrations, individually and as a mixture, and depressive symptoms, and to assess effect modification by PSS-4 scores, adjusting for confounders. RESULTS: Baseline perfluorodecanoic acid concentrations were associated with greater depressive symptoms at the 20-month follow-up, but associations for other PFAS were null. The PFAS were not associated with depressive symptoms when evaluated as a mixture. The association between the 90th percentile (vs. 50th percentile) of the PFAS mixture with CES-D scores was null at the 10th (ß = 0.03; 95 % CrI = 0.20, 0.25), 50th (ß = 0.02; 95 % CrI = -0.16, 0.19), and 90th (ß = 0.01; 95 % CrI = 0.18, 0.20) percentiles of PSS-4 scores, suggesting perceived stress did not modify the PFAS mixture. CONCLUSION: In this prospective cohort study, PFAS concentrations-assessed individually or as a mixture-were not appreciably associated with depressive symptoms, and there was no evidence of effect modification by perceived stress.

Hair product use and urinary biomarker concentrations of non-persistent endocrine disrupting chemicals among reproductive-aged Black women.

BACKGROUND: Studies have shown an association between hair product use and adverse health outcomes. Scientists have hypothesized that exposure to endocrine-disrupting chemicals (EDCs) drives these associations, but few studies have directly evaluated associations between hair product use and biomarkers of EDCs. Even more limited are studies of Black women, who frequently use EDC-containing products (e.g., hair relaxers). OBJECTIVE: We estimated associations between hair product use and EDC biomarker concentrations. METHODS: We leveraged cross-sectional data from the Study of Environment, Lifestyle, and Fibroids, a cohort of females aged 23-34 years who self-identified as Black/African American from the Detroit-metropolitan area (USA; n = 425). On structured questionnaires, participants reported their past 24-h and past 12-month use of hair products, including relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food. We quantified urinary concentrations of 19 phthalate/phthalate alternative metabolites, 7 phenols, and 4 parabens using high performance liquid chromatography isotope dilution tandem mass spectrometry. EDC biomarker concentrations were creatinine-adjusted and natural log-transformed. We used multivariable linear regression to estimate mean percent differences in EDC biomarker concentrations and 95% confidence intervals (CIs) associated with hair product use, adjusting for sociodemographic confounders. RESULTS: Hair product use was associated with greater concentrations of multiple EDC biomarkers. Notably, use of hair products in the previous 24 h (compared with non-use) was associated with 16.2% (95% CI = 0.7%, 35.9%), 35.0% (95% CI = 2.6%, 77.6%), and 32.3% (95% CI = 8.8%, 92.0%) higher concentrations of mono-isobutyl phthalate, methyl paraben, and ethyl paraben, respectively. Use of hair relaxers/straighteners/perms, styling products, moisturizers, oils, and hair food in the past 12 months was also associated with higher concentrations of multiple phthalate, phenol, and paraben biomarkers. CONCLUSION: Hair product use was associated with higher biomarker concentrations of multiple phthalates, phenols, and parabens. These findings suggest that hair products are potentially important exposure sources for hormonally-active chemicals among Black women.

Non-persistent endocrine disrupting chemical mixtures and uterine leiomyomata in the study of environment, lifestyle and fibroids (SELF).

BACKGROUND: Results of studies investigating associations between individual endocrine-disrupting chemicals (EDCs) and incidence of uterine leiomyomata (UL), a hormone-dependent gynecological condition, have been inconsistent. However, few studies have evaluated simultaneous exposure to a mixture of EDCs with UL incidence. METHODS: We conducted a case-cohort analysis (n = 708) of data from the Study of the Environment, Lifestyle and Fibroids (SELF), a prospective cohort study. Participants were aged 23-35 years at enrollment, had an intact uterus, and identified as Black or African American. We measured biomarker concentrations of 21 non-persistent EDCs, including phthalates, phenols, parabens, and triclocarban, in urine collected at baseline, 20-month, and 40-month clinic visits. We ascertained UL incidence and characteristics using ultrasounds at baseline and approximately every 20 months through 60 months. We used probit Bayesian Kernel Machine Regression (BKMR-P) to evaluate joint associations between EDC mixtures with cumulative UL incidence. We estimated the mean difference in the probit of UL incidence over the study period, adjusting for baseline age, education, years since last birth, parity, smoking status and body mass index. We converted probit estimates to odds ratios for ease of interpretation. RESULTS: We observed that urinary concentrations of the overall EDC mixture were inversely associated with UL incidence in the overall mixtures model, with the strongest inverse associations at the 70th percentile of all biomarkers compared with their 50th percentile (odds ratio = 0.59; 95% confidence interval: 0.36, 0.96). Strongest contributors to the joint association for the mixture were bisphenol S (BPS), ethyl paraben (EPB), bisphenol F (BPF) and mono (2-ethyl-5-carboxypentyl) phthalate (MECPP), which each demonstrated inverse associations except for MECPP. There was suggestive evidence of an interaction between MECPP and EPB. CONCLUSION: In this prospective ultrasound study, we observed evidence of an inverse association between the overall mixture of urinary biomarker concentrations of non-persistent EDCs with UL incidence.

Associations of per- and polyfluoroalkyl substances with uterine leiomyomata incidence and growth: a prospective ultrasound study.

BACKGROUND: Per- and polyfluoroalkyl substances (PFAS) are endocrine-disrupting chemicals used in commercial and consumer products. OBJECTIVE: We evaluated PFAS exposure in relation to incidence and growth of uterine leiomyomata (UL), hormone-dependent neoplasms that are associated with severe gynecologic morbidity. METHODS: We studied 1158 participants in the Study of Environment, Lifestyle, and Fibroids, a Detroit-based prospective cohort study of Black females aged 23-35 years at enrollment (2010-2012). At enrollment and four subsequent visits during 10 years of follow-up, participants attended in-person clinic visits, completed questionnaires, provided non-fasting blood samples, and underwent ultrasound for UL detection. We quantified 7 PFAS in baseline plasma samples using mass spectrometry. We used Cox regression and probit Bayesian kernel machine regression to estimate individual and joint effects of PFAS on UL incidence. We fit linear mixed models to estimate effects of individual PFAS on UL growth. We stratified by parity, an important route of PFAS elimination and determinant of UL. RESULTS: In individual PFAS analyses, we observed inverse associations for perfluorodecanoate (PFDA; ≥0.3 vs. <0.2 ng/ml: hazard ratio [HR] = 0.74; 95% confidence interval [CI]: 0.54-1.00) and perfluoroundecanoate (detected vs. non-detected: HR = 0.78; 95% CI: 0.61-1.01) and a weak positive association for perfluorohexane sulfonate (≥1 vs. <0.6 ng/ml: HR = 1.17; 95% CI: 0.85-1.61), while perfluorooctane sulfonate, perfluorooctanoate, perfluorononanoate (PFNA), and 2-N-methyl-perfluorooctane sulfonamido acetate (MeFOSAA) showed little association with UL incidence. The PFAS mixture was inversely associated with UL incidence, a finding driven by MeFOSAA and PFDA; however, PFNA was positively associated with UL incidence. The inverse association for PFDA and positive association for PFNA were stronger among nulliparous participants. Most PFAS showed slight inverse associations with UL growth. IMPACT STATEMENT: In this prospective ultrasound study of 1158 Black females aged 23-35 years at enrollment, we conducted a mixtures analysis to account for co-pollutant confounding and interaction. MeFOSAA and PFDA concentrations were inversely associated with UL incidence, while PFNA concentrations were positively associated with UL incidence. Concentrations of most PFAS were associated with decreased UL growth. This study contributes data to the sparse literature on PFAS exposure and UL development.

Parental Mental Health and Childhood Respiratory Outcomes in a Severe Bronchiolitis Cohort.

Parental mental health conditions appear to contribute to the development of childhood respiratory illness. We investigated the relationship between parental mental health and childhood respiratory illness using data from a 17-center prospective cohort study of infants hospitalized with bronchiolitis between 2011 and 2014 (n = 921). Among 779 (84.6%) participants with self-reported parental mental health history data, 184 (23.6%) had parental history of depression and 155 (19.9%) had anxiety. Multivariable analyses found that both parental history of depression (hazard ratio [HR] 1.41, 95% confidence interval [CI] 1.01-1.99) and anxiety (HR 1.28, 95% CI 1.08-1.52) were associated with an increased risk of recurrent wheezing by age 3 years. However, only parental history of anxiety was associated with asthma by age 5 years (odds ratio 1.79, 95% CI 1.25-2.55). Further research on exposure severity, other early life stressors, and effective methods of parental psychosocial support is needed to develop targeted risk factor prevention strategies to reduce the burden of childhood respiratory illness.

Application of Asthma Prediction Tools in a Cohort of Infants with Severe Bronchiolitis.

Background: Severe bronchiolitis is a strong childhood asthma risk factor. Early and accurate asthma prediction is key. We applied the Asthma Predictive Index (API), the modified Asthma Predictive Index (mAPI), and the Pediatric Asthma Risk Score (PARS) in a cohort of high-risk infants to predict asthma at age 6 years. Methods: We conducted a 17-center cohort of infants (age <1 year) hospitalized with severe bronchiolitis during 2011-2014. We used only infancy data to predict asthma at age 6 years. Results: The prevalence of parent-reported asthma at age 6 years was 328/880 (37%). The prevalences of a positive index/score for stringent and loose API, mAPI, and PARS were 21%, 51%, 11%, and 34%, respectively. Area under the receiver operating characteristic curves [95% confidence interval (CI)] ranged from 0.57 (95% CI 0.55-0.60) for mAPI to 0.66 (95% CI 0.63-0.70) for PARS. Conclusions: An asthma prediction tool for high-risk infants is needed to identify those who would benefit most from asthma prevention interventions.

COVID-19 vaccination and menstrual cycle characteristics: A prospective cohort study.

We prospectively examined the association between COVID-19 vaccination and menstrual cycle characteristics in an internet-based prospective cohort study. We included a sample of 1,137 participants who enrolled in Pregnancy Study Online (PRESTO), a preconception cohort study of couples trying to conceive, during January 2021-August 2022. Eligible participants were aged 21-45 years, United States or Canadian residents, and trying to conceive without fertility treatment. At baseline and every 8 weeks for up to 12 months, participants completed questionnaires on which they provided information on COVID-19 vaccination and menstrual cycle characteristics, including cycle regularity, cycle length, bleed length, heaviness of bleed, and menstrual pain. We fit generalized estimating equation (GEE) models with a log link function and Poisson distribution to estimate the adjusted risk ratio (RR) for irregular cycles associated with COVID-19 vaccination. We used linear regression with GEE to estimate adjusted mean differences in menstrual cycle length associated with COVID-19 vaccination. We adjusted for sociodemographic, lifestyle, medical and reproductive factors. Participants had 1.1 day longer menstrual cycles after receiving the first dose of COVID-19 vaccine (95 % CI: 0.4, 1.9) and 1.3 day longer cycles after receiving the second dose (95 % CI: 0.2, 2.5). Associations were attenuated at the second cycle post-vaccination. We did not observe strong associations between COVID-19 vaccination and cycle regularity, bleed length, heaviness of bleed, or menstrual pain. In conclusion, COVID-19 vaccination was associated with a ∼1 day temporary increase in menstrual cycle length, but was not appreciably associated with other menstrual cycle characteristics.

Infant Exposure to Acid Suppressant Medications Increases Risk of Recurrent Wheeze and Asthma in Childhood.

BACKGROUND: Acid suppressant medications (ASMs) are commonly prescribed in infancy. Little is known about the relationship between ASM exposure and risk of childhood asthma and atopic conditions. OBJECTIVE: We sought to examine the association between infant ASM exposure and risk for developing recurrent wheeze, allergen sensitization, and asthma in early childhood. METHODS: We used data from a diverse, multicenter, prospective cohort study of 921 infants with a history of bronchiolitis. ASM exposure (histamine-2 receptor antagonists and/or proton pump inhibitors) during infancy (age: <12 months) was ascertained by parent report and medical record review. The outcomes were recurrent wheeze by age 3 years, early childhood allergen sensitization (serum specific IgE), and asthma by age 6 years. We constructed multivariable Cox proportional hazards models and multivariable logistic regression models adjusting for multiple confounders. RESULTS: Of the 921 children in the cohort, 202 (22%) were exposed to ASMs during infancy. Compared with unexposed children, those exposed to ASM were more likely to develop recurrent wheeze by age 3 years (adjusted hazard ratio: 1.58, 95% confidence interval [CI]: 1.20-2.08, P = .001) and asthma by age 6 years (adjusted odds ratio: 1.66, 95% CI: 1.22-2.27, P = .001). ASM exposure during infancy was not significantly associated with the development of early childhood allergen sensitization (adjusted odds ratio: 1.00, 95% CI: 0.70-1.44, P = .99). CONCLUSIONS: Although exposure to ASMs during infancy does not increase the risk of allergen sensitization in early childhood, ASM exposure during infancy increases the risk of recurrent wheeze and asthma during early childhood.

Phthalate and novel plasticizer concentrations in food items from U.S. fast food chains: a preliminary analysis.

BACKGROUND: Fast food consumption is associated with biomarkers of ortho-phthalates exposures. However, the chemical content of fast food is unknown; certain ortho-phthalates (i.e., di-n-butyl phthalate (DnBP) and di(2-ethylhexyl) phthalate (DEHP)) have been phased out and replaced with other plasticizers (e.g., dioctyl terephthalate (DEHT)). OBJECTIVE: We conducted a preliminary study to examine ortho-phthalate and replacement plasticizer concentrations in foods and food handling gloves from U.S. fast food restaurants. METHODS: We obtained hamburgers, fries, chicken nuggets, chicken burritos, cheese pizza (n = 64 food samples) and gloves (n = 3) from restaurants and analyzed them for 11 chemicals using gas chromatography mass spectrometry. RESULTS: We found DEHT at the highest concentrations in both foods (n = 19; median = 2510 µg/kg; max = 12,400 µg/kg) and gloves (n = 3; range: 28-37% by weight). We detected DnBP and DEHP in 81% and 70% of food samples, respectively. Median DEHT concentrations were significantly higher in burritos than hamburgers (6000 µg/kg vs. 2200 µg/kg; p < 0.0001); DEHT was not detected in fries. Cheese pizza had the lowest levels of most chemicals. SIGNIFICANCE: To our knowledge, these are the first measurements of DEHT in food. Our preliminary findings suggest that ortho-phthalates remain ubiquitous and replacement plasticizers may be abundant in fast food meals. IMPACT STATEMENT: A selection of popular fast food items sampled in this study contain detectable levels of replacement plasticizers and concerning ortho-phthalates. In addition, food handling gloves contain replacement plasticizers, which may be a source of food contamination. These results, if confirmed, may inform individual and regulatory exposure reduction strategies.

Correlates of whole blood metal concentrations among reproductive-aged Black women.

BACKGROUND: Metals may influence reproductive health, but few studies have investigated correlates of metal body burden among reproductive-aged women outside of pregnancy. Furthermore, while there is evidence of racial disparities in exposure to metals among U.S. women, there is limited research about correlates of metal body burden among Black women. OBJECTIVE: To identify correlates of whole blood metal concentrations among reproductive-aged Black women. METHODS: We analyzed cross-sectional data from a cohort of 1664 Black women aged 23-35 years in Detroit, Michigan, 2010-2012. We collected blood samples and questionnaire data. We measured concentrations of 17 metals in whole blood using inductively-coupled plasma-mass spectrometer-triple quadrupole and total mercury using Direct Mercury Analyzer-80. We used multivariable linear regression models to identify sociodemographic, environmental, reproductive, and dietary correlates of individual metal concentrations. RESULTS: In adjusted models, age was positively associated with multiple metals, including arsenic, cadmium, and mercury. Education and income were inversely associated with cadmium and lead. Current smoking was strongly, positively associated with cadmium and lead. Alcohol intake in the past year was positively associated with arsenic, barium, copper, lead, mercury, vanadium, and zinc. Having pumped gasoline in the past 24 h was positively associated with cadmium, chromium, and molybdenum. Having lived in an urban area for the majority of residence in Michigan was positively associated with arsenic, lead, and nickel. Higher water intake in the past year was positively associated with several metals, including lead. Fish intake in the past year was positively associated with arsenic, cesium, and mercury. We also observed associations with body mass index, season, and other environmental, reproductive, and dietary factors. SIGNIFICANCE: We identified potential sources of exposure to metals among reproductive-aged Black women. Our findings improve understanding of exposures to metals among non-pregnant reproductive-aged women, and can inform policies in support of reducing disparities in exposures. IMPACT STATEMENT: There are racial disparities in exposures to metals. We analyzed correlates of blood metal concentrations among reproductive-aged Black women in the Detroit, Michigan metropolitan area. We identified sociodemographic, anthropometric, lifestyle, environmental, reproductive, and dietary correlates of metal body burden. Age was positively associated with several metals. Education and income were inversely associated with cadmium and lead, indicating socioeconomic disparities. We identified potential exposure sources of metals among reproductive-aged Black women, including smoking, environmental tobacco smoke, pumping gasoline, living in an urban area, and intake of alcohol, water, fish, and rice.