Childhood adversity and time-to-pregnancy in a preconception cohort.

We examined the association between childhood adversity and fecundability (the per-cycle probability of conception), and the extent to which childhood social support modified this association. We used data from 6,318 female participants aged 21-45 years in Pregnancy Study Online (PRESTO), a North American prospective preconception cohort study (2013-2022). Participants completed a baseline questionnaire, bimonthly follow-up questionnaires (until pregnancy or a censoring event), and a supplemental questionnaire on experiences across the life course including adverse childhood experiences (ACE) and social support (using the modified Berkman-Syme Social Network Index [SNI]). We used proportional probabilities regression models to compute fecundability ratios (FR) and 95% confidence intervals (CI), adjusting for potential confounders and precision variables. Adjusted FRs for ACE scores 1-3 and ≥4 vs. 0 were 0.91 (95% CI: 0.85, 0.97) and 0.84 (95% CI: 0.77, 0.91), respectively. FRs for ACE scores ≥4 vs. 0 were 0.86 (95% CI: 0.78, 0.94) among participants reporting high childhood social support (SNI ≥4) and 0.78 (95% CI: 0.56, 1.07) among participants reporting low childhood social support (SNI <4). Our findings confirm results from two previous studies and indicate that high childhood social support slightly buffered the effects of childhood adversity on fecundability.

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.

A Prospective Cohort Study of Persistent Endocrine Disrupting Chemicals and Perceived Stress.

Persistent endocrine disrupting chemicals (EDCs) can dysregulate the stress response. We evaluated associations between persistent EDCs and perceived stress among participants from the Study of Environment, Lifestyle and Fibroids (n=1,394), a prospective cohort study of Black women. Participants completed the Perceived Stress Scale (PSS-4) at baseline, and every 20 months through 60 months (range of scores: 0-16); higher scores indicated higher stress. EDCs, including per- and polyfluoroalkyl substances (PFAS), polychlorinated biphenyls (PCBs), polybrominated diphenyl ethers (PBDEs), and organochlorine pesticides, were quantified in plasma samples at baseline. We fit Bayesian Kernel Machine Regression (BKMR) and linear mixed effects models to estimate associations of EDCs (as a mixture and individually) with PSS-4 scores at baseline and at each follow-up visit, respectively. Increasing percentiles of the mixture were not strongly associated with PSS-4 scores at baseline, and no interactions were observed among EDCs. Several individual EDCs (e.g., PFDA, PCB 118, PBDE 99) were associated with higher PSS-4 scores at baseline or follow-up, while other EDCs (e.g., PCB 138/158) were associated with lower PSS-4 scores at baseline or follow-up. The directionality of associations for individual EDCs was inconsistent across follow-up visits. In conclusion, specific EDCs may be associated with perceived stress in Black women.

Hypertension, Cardiovascular Risk Factors, and Uterine Fibroid Diagnosis in Midlife.

Importance: Fibroids are benign neoplasms associated with severe gynecologic morbidity. There are no strategies to prevent fibroid development. Objective: To examine associations of hypertension, antihypertensive treatment, anthropometry, and blood biomarkers with incidence of reported fibroid diagnosis in midlife. Design, Setting, and Participants: The Study of Women's Health Across the Nation is a prospective, multisite cohort study in the US. Participants were followed-up from enrollment (1996-1997) through 13 semiannual visits (1998-2013). Participants had a menstrual period in the last 3 months, were not pregnant or lactating, were aged 42 to 52 years, were not using hormones, and had a uterus and at least 1 ovary. Participants with prior fibroid diagnoses were excluded. Data analysis was performed from November 2022 to February 2024. Exposures: Blood pressure, anthropometry, biomarkers (cholesterol, triglycerides, and C-reactive protein), and self-reported antihypertensive treatment at baseline and follow-up visits were measured. Hypertension status (new-onset, preexisting, or never [reference]) and hypertension treatment (untreated, treated, or no hypertension [reference]) were categorized. Main Outcomes and Measures: Participants reported fibroid diagnosis at each visit. Discrete-time survival models estimated hazard ratios (HRs) and 95% CIs for associations of time-varying hypertension status, antihypertensive treatment, anthropometry, and biomarkers with incident reported fibroid diagnoses. Results: Among 2570 participants without a history of diagnosed fibroids (median [IQR] age at screening, 45 [43-48] years; 1079 [42.1%] college educated), 526 (20%) reported a new fibroid diagnosis during follow-up. Risk varied by category of hypertension treatment: compared with those with no hypertension, participants with untreated hypertension had a 19% greater risk of newly diagnosed fibroids (HR, 1.19; 95% CI, 0.91-1.57), whereas those with treated hypertension had a 20% lower risk (HR, 0.80; 95% CI, 0.56-1.15). Among eligible participants with hypertension, those taking antihypertensive treatment had a 37% lower risk of newly diagnosed fibroids (HR, 0.63; 95% CI, 0.38-1.05). Risk also varied by hypertension status: compared with never-hypertensive participants, participants with new-onset hypertension had 45% greater risk of newly diagnosed fibroids (HR, 1.45; 95% CI, 0.96-2.20). Anthropometric factors and blood biomarkers were not associated with fibroid risk. Conclusions and Relevance: Participants with untreated and new-onset hypertension had increased risk of newly diagnosed fibroids, whereas those taking antihypertensive treatment had lower risk, suggesting that blood pressure control may provide new strategies for fibroid prevention.

Evaluating participant engagement in a preconception cohort study in relation to the Dobbs decision.

BACKGROUND: On June 24th, 2022, the United States (US) Supreme Court's ruling in Dobbs v. Jackson, et al. (hereafter, the Dobbs decision) removed federal-level protections for induced abortion, sparking concerns about reproductive rights and health privacy. Although other pregnancy outcomes (e.g. spontaneous abortion, ectopic pregnancy) are not explicit targets of post-Dobbs abortion bans, study participants may be worried about how their reproductive health data are used by researchers in the post-Dobbs era. OBJECTIVE: To evaluate the extent to which the Dobbs decision influenced participant's engagement in a preconception cohort study. METHODS: We leveraged data spanning 20 weeks before and after the Dobbs decision (4 February 2022, to 11 November 2022) from US participants in Pregnancy Study Online (PRESTO), an internet-based prospective preconception cohort study of couples attempting conception. We categorised participants' state-level abortion access by residential location: banned or restricted rights; limited access; and protected rights. We evaluated three participant engagement outcomes: follow-up questionnaire completion; report of a pregnancy; and clicking on the invitation link for a fertility-tracking app. We fit separate linear regression models and restricted cubic splines to compare outcome prevalence before and after the Dobbs decision by state-level abortion category. RESULTS: A total of 585 newly enrolled participants and 1247 already-enrolled participants received 2802 invitations to complete a follow-up questionnaire. In states with limited or protected abortion rights, we observed little change in participant engagement. In states with banned or restricted abortion rights, however, we observed a 27.12 percentage point reduction (95% confidence interval -43.68, -10.51) in the prevalence of clicking on the invitation link for the fertility-tracking app comparing the post- versus pre-Dobbs periods. CONCLUSIONS: There was some evidence of reduced participant engagement after the Dobbs decision in states with banned or restricted abortion rights, indicating potentially deleterious effects on the conduct of reproductive health studies.

Study protocol for the implementation of Centering Patients with Fibroids, a novel group education and empowerment program for patients with symptomatic uterine fibroids.

BACKGROUND: Black women and people with uteri have utilized collectivistic and relational practices to improve health outcomes in the face of medical racism and discrimination for decades. However, there remains a need for interventions to improve outcomes of uterine fibroids, a condition that disproportionately impacts Black people with uteri. Leveraging personalized approaches alongside evidence that demonstrates the positive impact of social and peer support on health outcomes, we adapted from CenteringPregnancy, an evidence based group prenatal care intervention, for the education and empowerment of patients with uterine fibroids. METHODS: The present report provides  an overview of the study design and planned implementation of CPWF in cohorts at Boston Medical Center and Emory University / Grady Memorial Hospital. After receiving training from the Centering Healthcare Institute (CHI), we adapted the 10-session CenteringPregnancy curriculum to an 8-session hybrid group intervention called Centering Patients with Fibroids (CPWF). The study began in 2022 with planned recruitment of six cohorts of 10-12 participants at each institution. We will conduct a mixed methods evaluation of the program using validated survey tools and qualitative methods, including focus groups and 1:1 interviews. DISCUSSION: To date, we have successfully recruited 4 cohorts at Boston Medical Center and are actively implementing BMC Cohort 5 and the first cohort at Emory University / Grady Memorial Hospital. Evaluation of the program is forthcoming.

Fibroids are non-cancerous smooth muscle tumors that disproportionate impact black women and gender expansive people. Our team adapted CenteringPregnancy, a group based model of prenatal care, to an education and empowerment program for peple with fibroids called Centering Patients with Fibroids (CPWF). This paper describes the development and implemation of the program at two academic hospitals serving diverse patients in Boston, Massachusetts and Atlanta, Georgia. To evaluate the successes and challenges of the program, we ask participants to complete surveys to learn more about their experience with having fibroids and also invite them to group feedback sessions or focus groups. We also interview other healthcare providers, team members, and hospital leadership on their knowledge and thoughts about the program. We hope to use the feedback to improve the program and make it available to more people across the country.

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.

Predictive models of miscarriage on the basis of data from a preconception cohort study.

OBJECTIVE: To use self-reported preconception data to derive models that predict the risk of miscarriage. DESIGN: Prospective preconception cohort study. SETTING: Not applicable. PATIENTS: Study participants were female, aged 21-45 years, residents of the United States or Canada, and attempting spontaneous pregnancy at enrollment during 2013-2022. Participants were followed for up to 12 months of pregnancy attempts; those who conceived were followed through pregnancy and postpartum. We restricted analyses to participants who conceived during the study period. EXPOSURE: On baseline and follow-up questionnaires completed every 8 weeks until pregnancy, we collected self-reported data on sociodemographic factors, reproductive history, lifestyle, anthropometrics, diet, medical history, and male partner characteristics. We included 160 potential predictor variables in our models. MAIN OUTCOME MEASURES: The primary outcome was a miscarriage, defined as pregnancy loss before 20 weeks of gestation. We followed participants from their first positive pregnancy test until miscarriage or a censoring event (induced abortion, ectopic pregnancy, loss of follow-up, or 20 weeks of gestation), whichever occurred first. We fit both survival and static models using Cox proportional hazards models, logistic regression, support vector machines, gradient-boosted trees, and random forest algorithms. We evaluated model performance using the concordance index (survival models) and the weighted F1 score (static models). RESULTS: Among the 8,720 participants who conceived, 20.4% reported miscarriage. In multivariable models, the strongest predictors of miscarriage were female age, history of miscarriage, and male partner age. The weighted F1 score ranged from 73%-89% for static models and the concordance index ranged from 53%-56% for survival models, indicating better discrimination for the static models compared with the survival models (i.e., the ability of the model to discriminate between individuals with and without miscarriage). No appreciable differences were observed across strata of miscarriage history or among models restricted to ≥8 weeks of gestation. CONCLUSION: Our findings suggest that miscarriage is not easily predicted on the basis of preconception lifestyle characteristics and that advancing age and a history of miscarriage are the most important predictors of incident miscarriage.

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.

A preconception cohort study of sugar-sweetened beverage consumption and semen quality.

BACKGROUND: Dietary factors, including high sugar intake, may have adverse effects on male reproduction. Studies of the association between sugar-sweetened beverage (SSB) intake and semen quality have reported inconsistent results. OBJECTIVE: We estimated the effects of SSB consumption on semen quality in a North American preconception cohort study. METHODS: We analyzed baseline data from 690 males (n = 1,247 samples) participating in Pregnancy Study Online (PRESTO) during 2015-2022. Participants aged ≥21 years completed a baseline questionnaire on which they reported information about intake of SSBs, including sodas, energy drinks, sports drinks, and fruit juices. After enrollment, we invited U.S. participants to a semen testing substudy, in which they collected and analyzed two samples using an at-home semen testing kit. We used linear regression models to estimate adjusted percent differences (%D) and 95% confidence intervals (CI) for associations of SSB intake with semen volume, sperm concentration, total sperm count (TSC), motility, and total motile sperm count (TMSC). We used modified Poisson regression models to estimate adjusted risk ratios (RRs) and 95% CIs for the association of SSB intake with World Health Organization semen parameter cut points. RESULTS: Relative to non-consumers of SSBs, those who consumed ≥7 SSBs/week had lower semen volume (%D = -6, 95% CI: -13, 0), sperm concentration (%D = -22, 95% CI: -38, 0), TSC (%D = -22, 95% CI: -38, -2), motility (%D = -4, 95% CI: -10, 2), and TMSC (%D = -25, 95% CI: -43, -2). High SSB consumers also had greater risks of low sperm concentration (≤16 million/mL; RR = 1.89, 95% CI: 1.11, 3.21), low TSC (≤39 million; RR = 1.75, 95% CI: 0.92, 3.33), low motility (≤42%; RR = 1.23, 95% CI: 0.87, 1.75) and low TMSC (≤21 million; RR = 1.95, 95% CI: 1.12, 3.38). Associations were stronger among participants with body mass index ≥ 25 kg/m2 . CONCLUSION: Greater SSB consumption was associated with reduced semen quality in a North American preconception cohort.

Long-Term Risk of Reintervention After Surgical Leiomyoma Treatment in an Integrated Health Care System.

OBJECTIVE: To compare long-term risk of reintervention across four uterus-preserving surgical treatments for leiomyomas and to assess effect modification by sociodemographic factors in a prospective cohort study in an integrated health care delivery system. METHODS: We studied a cohort of 10,324 patients aged 18-50 (19.9% Asian, 21.2% Black, 21.3% Hispanic, 32.5% White, 5.2% additional races and ethnicities) who had a first uterus-preserving procedure (abdominal, laparoscopic, or vaginal myomectomy [referred to as myomectomy]; hysteroscopic myomectomy; endometrial ablation; uterine artery embolization) after leiomyoma diagnosis in the 2009-2021 electronic health records of Kaiser Permanente Northern California. We followed up patients until reintervention (second uterus-preserving procedure or hysterectomy) or censoring. We used a Kaplan-Meier estimator to calculate the cumulative incidence of reintervention and Cox regression models to estimate hazard ratios and 95% CIs comparing rates of reintervention across procedures, adjusting for age, parity, race and ethnicity, body mass index (BMI), Neighborhood Deprivation Index, and year. We also assessed effect modification by demographic characteristics. RESULTS: Median follow-up was 3.8 years (interquartile range 1.8-7.4 years). Index procedures were 18.0% (1,857) hysteroscopic myomectomies, 16.2% (1,669) uterine artery embolizations, 21.4% (2,211) endometrial ablations, and 44.4% (4,587) myomectomies. Accounting for censoring, the 7-year reintervention risk was 20.6% for myomectomy, 26.0% for uterine artery embolization, 35.5% for endometrial ablation, and 37.0% for hysteroscopic myomectomy; 63.2% of reinterventions were hysterectomies. Within each procedure type, reintervention rates did not vary by BMI, race and ethnicity, or Neighborhood Deprivation Index. However, rates of reintervention after uterine artery embolization, endometrial ablation, and hysteroscopic myomectomy decreased with age, and reintervention rates for hysteroscopic myomectomy were higher for parous than nulliparous patients. CONCLUSION: Long-term reintervention risks for uterine artery embolization, endometrial ablation, and hysteroscopic myomectomy are greater than for myomectomy, with potential variation by patient age and parity but not BMI, race and ethnicity, or Neighborhood Deprivation Index.

Personal Care Products, Socioeconomic Status, and Endocrine-Disrupting Chemical Mixtures in Black Women.

Personal care products (PCPs) are sources of exposure to endocrine-disrupting chemicals (EDCs) among women, and socioeconomic status (SES) may influence these exposures. Black women have inequitable exposure to EDCs from PCP use, but no study has investigated how exposure to EDCs through PCPs may vary by SES, independent of race. Using data from the Study of Environment, Lifestyle, and Fibroids, a cohort of reproductive-aged Black women (n = 751), we quantified associations between PCPs and urinary biomarker concentrations of EDC mixtures (i.e., phthalates, phenols, parabens) within SES groups, defined using k-modes clustering based on education, income, marital status, and employment. Information about PCP use and SES was collected through questionnaires and interviews. We used principal component analysis to characterize the EDC mixture profiles. Stratified linear regression models were fit to assess associations between PCP use and EDC mixture profiles, quantified as mean differences in PC scores, by SES group. Associations between PCP use and EDC mixture profiles varied by SES group; e.g., vaginal powder use was associated with a mixture of phenols among lower SES women, whereas this association was null for higher SES women. Findings suggest that SES influences PCP EDC exposure in Black women, which has implications for public health interventions.

Cadmium exposure and cardiovascular disease risk: A systematic review and dose-response meta-analysis.

Exposure to toxic metals is a global public health threat. Among other adverse effects, exposure to the heavy metal cadmium has been associated with greater risk of cardiovascular disease (CVD). Nonetheless, the shape of the association between cadmium exposure and CVD risk is not clear. This systematic review summarizes data on the association between cadmium exposure and risk of CVD using a dose-response approach. We carried out a literature search in PubMed, Web of Science, and Embase from inception to December 30, 2023. Inclusion criteria were: studies on adult populations, assessment of cadmium exposure, risk of overall CVD and main CVD subgroups as endpoints, and observational study design (cohort, cross-sectional, or case-control). We retrieved 26 eligible studies published during 2005-2023, measuring cadmium exposure mainly in urine and whole blood. In a dose-response meta-analysis using the one-stage method within a random-effects model, we observed a positive association between cadmium exposure and risk of overall CVD. When using whole blood cadmium as a biomarker, the association with overall CVD risk was linear, yielding a risk ratio (RR) of 2.58 (95 % confidence interval-CI 1.78-3.74) at 1 µg/L. When using urinary cadmium as a biomarker, the association was linear until 0.5 µg/g creatinine (RR = 2.79, 95 % CI 1.26-6.16), after which risk plateaued. We found similar patterns of association of cadmium exposure with overall CVD mortality and risks of heart failure, coronary heart disease, and overall stroke, whereas for ischemic stroke there was a positive association with mortality only. Overall, our results suggest that cadmium exposure, whether measured in urine or whole blood, is associated with increased CVD risk, further highlighting the importance of reducing environmental pollution from this heavy metal.

Association between job control and time to pregnancy in a preconception cohort.

OBJECTIVE: To evaluate associations between low job control (operationalized as job independence and freedom to make decisions) and time to pregnancy. Low job control, a form of workplace stress, is associated with adverse health outcomes ranging from cardiovascular disease to premature mortality; few studies have specifically examined its association with reproductive outcomes. DESIGN: We used data from Pregnancy Study Online, an internet-based preconception cohort study of couples trying to conceive in the United States and Canada. We estimated fecundability ratios (FRs) and 95% confidence intervals (CIs) via proportional probability regression models, adjusting for sociodemographic and behavioral characteristics. SETTING: Not applicable (Web-based study). PATIENTS: Participants self-identified as female, were aged 21-45 years, and reported ≤6 cycles of pregnancy attempt time at enrollment (2018-2022). EXPOSURE: We assessed job control by matching participants' baseline self-reported occupation and industry with standardized occupation codes from the National Institute for Occupational Safety and Health's Industry and Occupation Computerized Coding System, then linking codes to O∗NET job exposure scores for job independence and freedom to make decisions. MAIN OUTCOME MEASURE: Our main outcome measure was fecundability. Participants completed self-administered questionnaires at baseline and every 8 weeks for up to 12 months or until reported pregnancy, whichever occurred first. RESULTS: Among 3,110 participants, lower job independence was associated with reduced fecundability. Compared with the fourth (highest) quartile, corresponding to the most job independence, FRs (95% CI) for first (lowest), second, and third quartiles were 0.92 (0.82-1.04), 0.84 (0.74-0.95), and 0.99 (0.88, 1.11), respectively. Lower freedom to make decisions was associated with slightly reduced fecundability (first vs. fourth quartile: FR = 0.92; 95% CI: 0.80-1.05). CONCLUSION: Lower job control, a work-related stressor, may adversely influence time to pregnancy. Because job control is a condition of work (i.e., not modifiable by individuals), these findings may strengthen arguments for improving working conditions as a means of improving worker health, including fertility.

The association between preconception cannabis use and gestational diabetes mellitus: The Preconception Period Analysis of Risks and Exposures Influencing health and Development (PrePARED) consortium.

BACKGROUND: The metabolic changes that ultimately lead to gestational diabetes mellitus (GDM) likely begin before pregnancy. Cannabis use might increase the risk of GDM by increasing appetite or promoting fat deposition and adipogenesis. OBJECTIVES: We aimed to assess the association between preconception cannabis use and GDM incidence. METHODS: We analysed individual-level data from eight prospective cohort studies. We identified the first, or index, pregnancy (lasting ≥20 weeks of gestation with GDM status) after cannabis use. In analyses of pooled individual-level data, we used logistic regression to estimate study-type-specific odds ratios (OR) and 95% confidence intervals (CI), adjusting for potential confounders using random effect meta-analysis to combine study-type-specific ORs and 95% CIs. Stratified analyses assessed potential effect modification by preconception tobacco use and pre-pregnancy body mass index (BMI). RESULTS: Of 17,880 participants with an index pregnancy, 1198 (6.7%) were diagnosed with GDM. Before the index pregnancy, 12.5% of participants used cannabis in the past year. Overall, there was no association between preconception cannabis use in the past year and GDM (OR 0.97, 95% CI 0.79, 1.18). Among participants who never used tobacco, however, those who used cannabis more than weekly had a higher risk of developing GDM than those who did not use cannabis in the past year (OR 2.65, 95% CI 1.15, 6.09). This association was not present among former or current tobacco users. Results were similar across all preconception BMI groups. CONCLUSIONS: In this pooled analysis of preconception cohort studies, preconception cannabis use was associated with a higher risk of developing GDM among individuals who never used tobacco but not among individuals who formerly or currently used tobacco. Future studies with more detailed measurements are needed to investigate the influence of preconception cannabis use on pregnancy complications.

Ambient air pollution and rate of spontaneous abortion.

Spontaneous abortion (SAB), defined as a pregnancy loss before 20 weeks of gestation, affects up to 30% of conceptions, yet few modifiable risk factors have been identified. We estimated the effect of ambient air pollution exposure on SAB incidence in Pregnancy Study Online (PRESTO), a preconception cohort study of North American couples who were trying to conceive. Participants completed questionnaires at baseline, every 8 weeks during preconception follow-up, and in early and late pregnancy. We analyzed data on 4643 United States (U.S.) participants and 851 Canadian participants who enrolled during 2013-2019 and conceived during 12 months of follow-up. We used country-specific national spatiotemporal models to estimate concentrations of particulate matter <2.5 µm (PM2.5), nitrogen dioxide (NO2), and ozone (O3) during the preconception and prenatal periods at each participant's residential address. On follow-up and pregnancy questionnaires, participants reported information on pregnancy status, including SAB incidence and timing. We fit Cox proportional hazards regression models with gestational weeks as the time scale to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for the association of time-varying prenatal concentrations of PM2.5, NO2, and O3 with rate of SAB, adjusting for individual- and neighborhood-level factors. Nineteen percent of pregnancies ended in SAB. Greater PM2.5 concentrations were associated with a higher incidence of SAB in Canada, but not in the U.S. (HRs for a 5 µg/m3 increase = 1.29, 95% CI: 0.99, 1.68 and 0.94, 95% CI: 0.83, 1.08, respectively). NO2 and O3 concentrations were not appreciably associated with SAB incidence. Results did not vary substantially by gestational weeks or season at risk. In summary, we found little evidence for an effect of residential ambient PM2.5, NO2, and O3 concentrations on SAB incidence in the U.S., but a moderate positive association of PM2.5 with SAB incidence in Canada.

Adherence to the Mediterranean-DASH Intervention for Neurodegenerative Delay (MIND) diet and exposure to selenium species: A cross-sectional study.

Selenium is a trace element found in many chemical forms. Selenium and its species have nutritional and toxicologic properties, some of which may play a role in the etiology of neurological disease. We hypothesized that adherence to the Mediterranean-Dietary Approach to Stop Hypertension Intervention for Neurodegenerative Delay (MIND) diet could influence intake and endogenous concentrations of selenium and selenium species, thus contributing to the beneficial effects of this dietary pattern. We carried out a cross-sectional study of 137 non-smoking blood donors (75 females and 62 males) from the Reggio Emilia province, Northern Italy. We assessed MIND diet adherence using a semiquantitative food frequency questionnaire. We assessed selenium exposure through dietary intake and measurement of urinary and serum concentrations, including speciation of selenium compound in serum. We fitted non-linear spline-based regression models to investigate the association between MIND diet adherence and selenium exposure concentrations. Adherence to the MIND diet was positively associated with dietary selenium intake and urinary selenium excretion, whereas it was inversely associated with serum concentrations of overall selenium and organic selenium, including serum selenoprotein P-bound selenium, the most abundant circulating chemical form of the metalloid. MIND diet adherence also showed an inverted U-shaped relation with inorganic selenium and particularly with its hexavalent form, selenate. Our results suggest that greater adherence to the MIND diet is non-linearly associated with lower circulating concentrations of selenium and of 2 potentially neurotoxic species of this element, selenoprotein P and selenate. This may explain why adherence to the MIND dietary pattern may reduce cognitive decline.

Residential exposure to magnetic fields from transformer stations and risk of childhood leukemia.

BACKGROUND: Several studies have documented an increased risk of leukemia among children exposed to magnetic fields from high-voltage power lines, with some evidence of dose-response relation. However, findings in some studies have been inconsistent, and data on the effects of different sources of exposure are lacking. In this study, we evaluated the relation of childhood leukemia risk to exposure to magnetic fields from transformer stations. METHODS: We conducted a population-based case-control study in a pediatric population of two Northern Italian provinces of Modena and Reggio Emilia. We included 182 registry-identified childhood leukemia cases diagnosed during 1998-2019 and 726 population controls matched on sex, year of birth, and province of residence. We assessed exposure by calculating distance from childhood residence to the nearest transformer station within a geographical information system, computing disease odds ratios (ORs) and 95% confidence intervals (CIs) using conditional logistic regression, adjusting for potential confounders. We evaluated exposure using two buffers (15 m and 25 m radius) and assessed two case groups: leukemia (all subtypes) and acute lymphoblastic leukemia (ALL). RESULTS: Residing within 15 m of a transformer station (vs. ≥15 m) was not appreciably associated with risk of leukemia (all subtypes) or ALL. We found similar results using a less stringent exposure buffer (25 m). Among children aged ≥5 years, the adjusted ORs were 1.3 (95% CI 0.1-12.8) for leukemia and 1.3 (95% CI 0.1-12.4) for ALL using the 15 m buffer, while they were 1.7 (95% CI 0.4-7.0) for leukemia and 0.6 (95% CI 0.1-4.8) for ALL using the 25 m buffer. CONCLUSIONS: While we found no overall association between residential proximity to transformer stations and childhood leukemia, there was some evidence for elevated risk of childhood leukemia among children aged ≥5 years. Precision was limited by the low numbers of exposed children.