ArticleNPJ digital medicine2019
Real-world menstrual cycle characteristics of more than 600,000 menstrual cycles.
Article in NPJ digital medicine, 2019. The graph could read no effect estimate from its abstract, so it casts no vote on the map. It is linked to trial NCT06750250 (The Effects of Aerobic Exercise on Rate Perceived Exertion, Performance Test Parameters and Behaviour During the Different Phases of Menstural Cycle), which is not on this map. Cited by 206 papers, 6 of them syntheses that pooled it.
What it found
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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.
The Effects of Aerobic Exercise on Rate Perceived Exertion, Performance Test Parameters and Behaviour During the Different Phases of Menstural Cycle
Who cites it
206 citing papers in PubMed, 6 syntheses or guidelines pooled it.
- Self-management strategies for menstrual cycle symptoms: a systematic review.BMC women's health · 2026Pooled it
- A systematic review of resting-state EEG across the menstrual cycle and its mental health relevance.Archives of women's mental health · 2026Pooled it
- Physiological influences on neurovascular coupling: A systematic review of multimodal imaging approaches and recommendations for future study designs.Experimental physiology · 2025Pooled it
- Menstrual disturbance associated with COVID-19 vaccines: A comprehensive systematic review and meta-analysis.PloS one · 2025Pooled it
- Pooled it
- Pooled it
- Influence of Gestational Age Measurement Technique on the Associations Between Maternal Characteristics and Birth Outcomes.Paediatric and perinatal epidemiology · 2026Trial
- Impact of The Menstrual Cycle on Physical Recovery after Small-Sided Games: A Crossover Study in Women's Soccer Players.Journal of sports science & medicine · 2025Trial
- Effects of Quercetin and Citrulline on Nitric Oxide Metabolites and Antioxidant Biomarkers in Trained Cyclists.Nutrients · 2025Trial
- The effect of quercetin and citrulline on cycling time trial performance.Journal of the International Society of Sports Nutrition · 2024Trial
- The effect of bodyweight exercise on 24-h glycemic responses determined by continuous glucose monitoring in healthy inactive adults: a randomized crossover study.Scientific reports · 2023Trial
- The Sprint-Interval Exercise Using a Spinning Bike Improves Physical Fitness and Ameliorates Primary Dysmenorrhea Symptoms Through Hormone and Inflammation Modulations: A Randomized Controlled Trial.Journal of sports science & medicine · 2022Trial
- Home pregnancy test sensitivity by test timing and cycle length with real-world use among pregnancy planners who conceived.Fertility and sterility · 2026Article
- Population-scale reconstruction of menopause dynamics reveals a physiological cliff at the final menstrual period.Nature medicine · 2026Article
- Article
- The association between PFAS exposure, menstrual cycle parameters, and reproductive hormones in adolescent girls.The Journal of clinical endocrinology and metabolism · 2026Observational
- Early-life exposures and risk of multiple gynecological diseases: evidence from a large community-based study of 272,706 women.BMC women's health · 2026Observational
- A Bayesian Modeling Approach to Optimize Longitudinal Biomarker Sampling Schedules Using Hormonal Data.American journal of human biology : the official journal of the Human Biology Council · 2026Article
- The progesterone to estradiol ratio predicts fear extinction in mice and humans.Neurobiology of stress · 2026Article
- Benchmarking machine learning architectures for menstrual recovery prediction using physiologically informed synthetic wearable data.Scientific reports · 2026Article
146 more citing papers are in PubMed but not listed here.
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
6 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
The use of apps that record detailed menstrual cycle data presents a new opportunity to study the menstrual cycle. The aim of this study is to describe menstrual cycle characteristics observed from a large database of cycles collected through an app and investigate associations of menstrual cycle characteristics with cycle length, age and body mass index (BMI). Menstrual cycle parameters, including menstruation, basal body temperature (BBT) and luteinising hormone (LH) tests as well as age and BMI were collected anonymously from real-world users of the Natural Cycles app. We analysed 612,613 ovulatory cycles with a mean length of 29.3 days from 124,648 users. The mean follicular phase length was 16.9 days (95% CI: 10-30) and mean luteal phase length was 12.4 days (95% CI: 7-17). Mean cycle length decreased by 0.18 days (95% CI: 0.17-0.18,
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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 OpenQuestion graph.