Publications by authors named "Kj Rothman"
Study Question: To what extent are self-reported diagnoses of food allergies associated with fecundability, the per-cycle probability of conception?
Summary Answer: Fecundability was not appreciably associated with self-reported food allergy diagnoses, number of food allergies, age at first diagnosis, or time since last allergic reaction.
What Is Known Already: Food allergies are atopic diseases that are characterized by an inappropriate immune response to a normally harmless dietary substance. While some studies have observed associations between atopic disorders and infertility, no study has examined the association between food allergies and fecundability, the per-cycle probability of conception.
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.
Background: The target trial framework was developed as a strategy to design and analyze observational epidemiologic studies with the aim of reducing bias due to analytic decisions. It involves designing a hypothetical randomized trial to answer a question of interest and systematically considering how to use observational data to emulate each trial component.
Aims: The primary aim of this paper is to provide a detailed example of the application of the target trial framework to a research question in oral epidemiology.
Background: The use of fertility indicators to predict ovulation has largely been studied for contraceptive purposes, while less so as fertility-promoting tools.
Objective: To investigate the association between fertility indicators and fecundability in Danish women trying to conceive.
Methods: Web-based preconception cohort study.
Studying the effect of duration of treatment on prognostic outcomes using real-world data is challenging because only people who survive for a long time can receive a treatment for a long time. Specifying a target trial helps overcome such challenge. We aimed to estimate the effect of different durations of treatment with antihypertensive drugs with anticholinergic properties (AC AHT) on the risk of vascular dementia and Alzheimer's disease by emulating a target trial using the UK CPRD GOLD database (2001-2017).
View Article and Find Full Text PDFStudy Question: Is cervical intraepithelial neoplasia (CIN) associated with reduced fecundability, defined as the probability of conceiving per menstrual cycle?
Summary Answer: Overall, we observed no meaningful association between CIN and fecundability, regardless of surgical status, although a recent diagnosis of moderate or severe CIN might be associated with slightly reduced fecundability for 2 years after diagnosis.
What Is Known Already: About 15% of couples experience infertility. Few studies have examined the influence of CIN on fertility, and the results have been inconsistent.
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.
Purpose: We describe constructs designed to protect the integrity of the results from comparative analyses using real-world data (RWD): staging and clean room.
Methods: Staging involves performing sequential preliminary analyses and evaluating the population size available and potential bias before conducting comparative analyses. A clean room involves restricted access to data and preliminary results, policies governing exploratory analyses and protocol deviations, and audit trail.
Objective: To assess risk of anaphylaxis among patients with type 2 diabetes mellitus who are initiating therapy with a glucagon-like peptide 1 receptor agonist (GLP-1 RA), with a focus on those starting lixisenatide therapy.
Research Design And Methods: A cohort study was conducted in three large, U.S.
Process guide for inferential studies using healthcare data from routine clinical practice to evaluate causal effects of drugs (PRINCIPLED): considerations from the FDA Sentinel Innovation Center.
BMJ
February 2024
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.
View Article and Find Full Text PDFStudy Question: To what extent do self-reported sleep duration and non-daytime work schedules in either partner affect the rate of spontaneous abortion (SAB)?
Summary Answer: Incidence of SAB had little association with female sleep duration and a modest positive association with male short sleep duration, female work at night, and discrepant work schedules among partners.
What Is Known Already: Several studies have reported an association between short sleep duration in either partner and reproductive health outcomes, including fecundability. Moreover, certain types of female occupational exposures during pregnancy have been associated with an increased risk of SAB.
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.
Objective: To examine the time trend of statistical inference, statistical reporting style of results, and effect measures from the abstracts of randomized controlled trials (RCTs).
Study Desgin And Settings: We downloaded 385,867 PubMed abstracts of RCTs from 1975 to 2021. We used text-mining to detect reporting of statistical inference (p-values, confidence intervals, significance terminology), statistical reporting style of results, and effect measures for binary outcomes, including time-to-event measures.
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: The APEX-IUD (Association of Perforation and Expulsion of Intrauterine Devices) study evaluated the association of postpartum timing of intrauterine device (IUD) insertion, breastfeeding, heavy menstrual bleeding, and IUD type (levonorgestrel-releasing vs copper) with risks of uterine perforation and IUD expulsion in usual clinical practice. We summarize the clinically important findings to inform counseling and shared decision making.
Methods: APEX-IUD was a real-world (using U.
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.
Few studies have evaluated the association between periodontitis and spontaneous abortion (SAB), and all had limitations. We used data from the Pregnancy Study Online (PRESTO), a prospective preconception cohort study of 3,444 pregnancy planners in the United States and Canada (2019-2022), to address this question. Participants provided self-reported data on periodontitis diagnosis, treatment, and symptoms of severity (i.
View Article and Find Full Text PDFWe 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.