ArticleJournal of medical Internet research2020
Menstrual Cycle Length and Patterns in a Global Cohort of Women Using a Mobile Phone App: Retrospective Cohort Study.
Article in Journal of medical Internet research, 2020. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 33 papers.
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Who cites it
33 citing papers in PubMed, 77 citations in OpenAlex.
- Monitoring Menstrual Health in Footballers: Considerations for Tracking Menstrual and Hormonal Contraceptive Cycles in the Field to Support Performance.Sports medicine (Auckland, N.Z.) · 2026Review
- Decoding menstrual health across the lifespan: a scoping review of digital health tools in research.medRxiv : the preprint server for health sciences · 2026Article
- Within-individual changes in BMI and menstrual irregularity: a cohort study using real-world data.BMC women's health · 2026Article
- Decoding menstrual health across the lifespan: a scoping review of digital health tools in research.npj women's health · 2026Article
- How to study the menstrual cycle as a continuous variable: Implementing phase-aligned cycle time scaling (PACTS) with the menstrualcycleR package.Psychoneuroendocrinology · 2025Article
- The Menstrual Cycle as a Vital Sign: a comprehensive review.F&S reviews · 2025Article
- Comparison of two ovulation tests to predict timing of the late follicular phase for menstrual cycle research in premenopausal females.Physiological reports · 2025Article
- Analysis of systemic effects of dioxin on human health through template-and-anchor modeling.PLoS computational biology · 2025Article
- Time to cycle regularity and health risks.Current opinion in endocrinology, diabetes, and obesity · 2024Review
- Menstrual Cycle Management and Period Tracker App Use in Millennial and Generation Z Individuals: Mixed Methods Study.Journal of medical Internet research · 2024Article
- Tampons as a source of exposure to metal(loid)s.Environment international · 2024Article
- Chronicling menstrual cycle patterns across the reproductive lifespan with real-world data.Scientific reports · 2024Article
- Seasonal variations of menstrual cycle length in a large, US-based, digital cohort.International journal of hygiene and environmental health · 2024Article
- Innovative Hematology Analysis Using Menstrual Blood.Medical devices (Auckland, N.Z.) · 2024Article
- A pharmacist's role in increasing access to menstrual products: an education and advocacy approach.Frontiers in reproductive health · 2024Article
- Diagnostic performance of screening mammography according to menstrual cycle among Asian women.Breast cancer research and treatment · 2023Article
- The Menstrual Cycle's Influence on Sleep Duration and Cardiovascular Health: A Comprehensive Review.Cureus · 2023Review
- Using Hormone Data and Age to Pinpoint Cycle Day within the Menstrual Cycle.Medicina (Kaunas, Lithuania) · 2023Article
- Menstrual cycle length variation by demographic characteristics from the Apple Women's Health Study.NPJ digital medicine · 2023Article
- Characterization of Self-reported Improvements in Knowledge and Health Among Users of Flo Period Tracking App: Cross-sectional Survey.JMIR mHealth and uHealth · 2023Article
Corrections and comments
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Authors and funding
2 authors at 1 institution in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThere is increasing information characterizing menstrual cycle length in women, but less information is available on the potential differences across lifestyle variables.
objectiveThis study aimed to describe differences in menstrual cycle length, variability, and menstrual phase across women of different ages and BMI among a global cohort of Flo app users. We have also reported on demographic and lifestyle characteristics across median cycle lengths.
methodsThe analysis was run based on the aggregated anonymized dataset from a menstrual cycle tracker and ovulation calendar that covers all phases of the reproductive cycle. Self-reported information is documented, including demographics, menstrual flow and cycle length, ovulation information, and reproductive health and diseases. Data from women aged ≥18 years and who had logged at least three cycles (ie, 2 completed cycles and 1 current cycle) in the Flo app were included (1,579,819 women).
resultsOf the 1.5 million users, approximately half (638,683/1,579,819, 40.42%) were aged between 18 and 24 years. Just over half of those reporting BMIs were in the normal range (18.5-24.9 kg/m
conclusionsOn a global scale, we have provided extensive evidence on the characteristics of women and their menstrual cycle length and patterns across different age and BMI groups. This information is necessary to support updates of current clinical guidelines around menstrual cycle length and patterns for clinical use in fertility programs.
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