ArticleNPJ digital medicine2023
Menstrual cycle length variation by demographic characteristics from the Apple Women's Health Study.
Article in NPJ digital medicine, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 37 papers, 3 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
37 citing papers in PubMed, 3 syntheses or guidelines pooled it, 52 citations in OpenAlex.
- The effects of hormone changes over the menstrual cycle on elite athlete performance: meta-analysis and suggested standardised protocol.Reproduction & fertility · 2026Pooled it
- Pooled it
- The effects of oral contraceptives on resting autonomic function and the autonomic response to physiological stressors: a systematic review.Clinical autonomic research : official journal of the Clinical Autonomic Research Society · 2023Pooled it
- Home pregnancy test sensitivity by test timing and cycle length with real-world use among pregnancy planners who conceived.Fertility and sterility · 2026Article
- 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
- The menstrual cycle through the lens of a wearable device: insights into physiology, sleep, and cycle variability.NPJ digital medicine · 2026Article
- Associations between self-reported personal care products use and menstrual cycle length and regularity in a US digital cohort.Environment international · 2026Article
- MENSTRUAL PATTERN CHANGES AMONG WOMEN DURING THE COVID-19 PANDEMIC IN IBADAN, A CROSS-SECTIONAL STUDY.Annals of Ibadan postgraduate medicine · 2026Article
- Considerations and practical recommendations for identifying perimenopause in longitudinal research.Psychoneuroendocrinology · 2026Review
- Variability of menstrual cycles by age, polycystic ovary syndrome, and early-life cycle irregularity in the apple Women's Health Study.American journal of obstetrics and gynecology · 2026Article
- Baseline vagal tone and pain reactivity: linking autonomic function to endogenous pain inhibition in women.Pain reports · 2026Article
- 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
- Mobile device data for the study of miscarriage and its causes.npj women's health · 2026Article
- The burden of endometriosis on quality of life in Danish women: an analysis of the Danish Blood Donor Study.BMC medicine · 2025Article
- The potential bidirectional relationship between long COVID and menstruation.Nature communications · 2025Article
- A survey assessing the impact of symptoms related to the menstrual cycle and perceptions of workplace productivity: considerations for employer-sponsored menstrual health programs.BMC women's health · 2025Article
- Digitally Enabled AI-Interpreted Salivary Ferning-Based Ovulation Prediction: Feasibility Study.Journal of medical Internet research · 2025Article
- Association between shift/night work and irregular periods and period pain among two cohorts of Australian women 16 years apart: findings from the Australian longitudinal study on women's health.International archives of occupational and environmental health · 2025Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
12 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
Menstrual characteristics are important signs of women's health. Here we examine the variation of menstrual cycle length by age, ethnicity, and body weight using 165,668 cycles from 12,608 participants in the US using mobile menstrual tracking apps. After adjusting for all covariates, mean menstrual cycle length is shorter with older age across all age groups until age 50 and then became longer for those age 50 and older. Menstrual cycles are on average 1.6 (95%CI: 1.2, 2.0) days longer for Asian and 0.7 (95%CI: 0.4, 1.0) days longer for Hispanic participants compared to white non-Hispanic participants. Participants with BMI ≥ 40 kg/m
Identifiers
What Socratic holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the Socratic graph.