Publications by authors named "Tanran R Wang"
Study Question: To what extent is male physical activity (PA) associated with fecundability (per-cycle probability of conception)?
Summary Answer: Preconception levels of vigorous, moderate, or total PA were not consistently associated with fecundability across Danish and North American cohorts, but there was suggestive evidence that bicycling with a 'soft, comfort seat' was associated with reduced fecundability in both cohorts, especially among males with greater BMI.
What Is Known Already: Among males, some studies indicate that moderate PA might improve fertility, whereas vigorous PA, especially bicycling, might be detrimental.
Study Design, Size, Duration: We assessed the association between male PA and fecundability among couples participating in two preconception cohort studies: SnartForaeldre.
Food frequency questionnaires require updating over time, due to population changes in diet, posing analytical challenges in consistently measuring diet in prospective studies. We compared reliability and agreement between nutrients in two versions of the National Cancer Institute's web-based Diet History Questionnaire (DHQ, III vs. II) in an ongoing North American preconception study.
View Article and Find Full Text PDFEvaluating participant engagement in a preconception cohort study in relation to the Dobbs decision.
Paediatr Perinat Epidemiol
September 2024
Article Synopsis
- - The Dobbs v. Jackson decision by the U.S. Supreme Court in June 2022 removed federal protections for abortion, raising concerns about reproductive rights and the use of health data in research.
- - This study analyzed data from a preconception cohort study, focusing on participant engagement before and after the Dobbs ruling, particularly in relation to their state's abortion access.
- - Results showed that in states with banned or restricted abortion rights, there was a significant 27.12 percentage point drop in participants clicking on a fertility-tracking app compared to states with limited or protected rights, indicating a decrease in engagement linked to the Dobbs decision.
Objective: To use self-reported preconception data to derive models that predict the risk of miscarriage.
Design: Prospective preconception cohort study.
Setting: Not applicable.
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.
Article Synopsis
- This study investigates the link between low job control—defined as limited job independence and decision-making freedom—and time to pregnancy among couples trying to conceive in the U.S. and Canada.
- Data were collected from a web-based study of 3,110 women aged 21-45, analyzing how their job-related stress might affect their ability to conceive.
- Results show that lower job independence correlates with a decrease in fecundability (likelihood of pregnancy), suggesting that job stress may negatively impact reproductive health.
Study Question: To what extent is preconception maternal or paternal coronavirus disease 2019 (COVID-19) vaccination associated with miscarriage incidence?
Summary Answer: COVID-19 vaccination in either partner at any time before conception is not associated with an increased rate of miscarriage.
What Is Known Already: Several observational studies have evaluated the safety of COVID-19 vaccination during pregnancy and found no association with miscarriage, though no study prospectively evaluated the risk of early miscarriage (gestational weeks [GW] <8) in relation to COVID-19 vaccination. Moreover, no study has evaluated the role of preconception vaccination in both male and female partners.
Article Synopsis
- Air pollution has potential adverse effects on fertility, but evidence is limited and varies across studies, making it unclear which specific pollutants are responsible.
- The study analyzed data from 8,747 fertility planners in the U.S. and Canada, focusing on the impact of different air pollutants on their chances of conceiving during a one-year period.
- Results showed no significant association between key pollutants like particulate matter, nitrogen dioxide, and ozone with fecundability rates in both countries, indicating that air pollution may not strongly influence fertility outcomes.
Objectives: To evaluate the association between preconception contraceptive use and miscarriage.
Design: Prospective cohort study.
Setting: Residents of the United States of America or Canada, recruited from 2013 until the end of 2022.
Objective: To evaluate the association between seasonal influenza vaccination and miscarriage using data from an ongoing, prospective cohort study.
Methods: We analyzed 2013-2022 data from PRESTO (Pregnancy Study Online), a prospective prepregnancy cohort study of female pregnancy planners and their male partners in the United States and Canada. Female participants completed a baseline questionnaire and then follow-up questionnaires every 8 weeks until pregnancy, during early and late pregnancy, and during the postpartum period.
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.
View Article and Find Full Text PDFObjective: To evaluate the association between anthropometric measures and semen parameters.
Design: Cross-sectional study.
Subjects: Male participants aged ≥21 years.
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.
View Article and Find Full Text PDFObjective: To assess the effect of randomization to FertilityFriend.com, a mobile computing fertility-tracking app, on fecundability.
Design: Parallel non-blinded randomized controlled trial nested within the Pregnancy Study Online (PRESTO), a North American preconception cohort.
Background: Many reproductive-aged North Americans use antibiotics in the weeks preceding conception or during early pregnancy. Antibiotic use may influence risk of spontaneous abortion (SAB) by disrupting the reproductive tract microbiome or treating harmful infections. However, this association has not been extensively studied.
View Article and Find Full Text PDFBackground: Psychological stress is prevalent among reproductive-aged men. Assessment of semen quality for epidemiological studies is challenging as data collection is expensive and cumbersome, and studies evaluating the effect of perceived stress on semen quality are inconsistent.
Objective: To examine the association between perceived stress and semen quality.
Background: Several studies indicate adverse effects of selected heat exposures on semen quality, but few studies have directly evaluated fertility as an endpoint.
Objective: We evaluated prospectively the association between male heat exposures and fecundability, the per-cycle probability of conception.
Materials And Methods: We analyzed data from 3041 couples residing in the United States or Canada who enrolled in a prospective preconception cohort study (2013-2021).
Purpose: Diet quality is increasingly recognized as important for human reproductive capacity. We studied the association between intake of protein-rich foods and risk of spontaneous abortion (SAB).
Methods: During 2013-2020, we recruited pregnancy planners from the United States and Canada (Pregnancy Study Online; PRESTO) and Denmark (SnartForaeldre.
Purpose: To evaluate the relationships among history of asthma, asthma severity, and spontaneous abortion (SAB).
Methods: Pregnancy Study Online is a preconception cohort study of North American couples. During the preconception period, female participants reported their history of physician-diagnosed asthma, age at first diagnosis, and use of asthma medications in the previous 4 weeks.
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.
View Article and Find Full Text PDFStudy Question: Can we derive adequate models to predict the probability of conception among couples actively trying to conceive?
Summary Answer: Leveraging data collected from female participants in a North American preconception cohort study, we developed models to predict pregnancy with performance of ∼70% in the area under the receiver operating characteristic curve (AUC).
What Is Known Already: Earlier work has focused primarily on identifying individual risk factors for infertility. Several predictive models have been developed in subfertile populations, with relatively low discrimination (AUC: 59-64%).
Air pollution and fecundability: Results from a Danish preconception cohort study.
Paediatr Perinat Epidemiol
January 2022
Background: Animal and epidemiologic studies indicate that air pollution may adversely affect fertility. Epidemiologic studies have been restricted largely to couples undergoing fertility treatment or have retrospectively ascertained time-to-pregnancy among pregnant women.
Objectives: We examined the association between residential ambient air pollution and fecundability, the per-cycle probability of conception, in a large preconception cohort of Danish pregnancy planners.
Study Question: To what extent is female preconception antibiotic use associated with fecundability?
Summary Answer: Preconception antibiotic use overall was not appreciably associated with fecundability.
What Is Known Already: Antibiotics are commonly used by women and are generally thought to be safe for use during pregnancy. However, little is known about possible effects of antibiotic use on fecundability, the per-cycle probability of conception.
Objective: To evaluate the associations of a history of diagnosed depression, current depressive symptoms, and recent use of psychotropic medications with semen quality and to consider mediation of the association between depression and semen quality by medication use.
Design: Prospective cohort study.
Setting: United States.