Evidence map›Paper›PMID 42185632›Full record

ArticleNPJ digital medicine2026

The menstrual cycle through the lens of a wearable device: insights into physiology, sleep, and cycle variability.

Alexander Gonzalez, Johanna J O'Day, Sarah C Johnson, Jeongeun Kim, Summer R Jasinski, Kristen E Holmes, Scott L Delp, Jennifer L Hicks

Abstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in NPJ digital medicine, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from 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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

8 authors.

Alexander Gonzalez *Wu Tsai Human Performance Alliance, Stanford University, Stanford, CA, USA. alex.gonzalez@stanford.edu.
Johanna J O'Day *Wu Tsai Human Performance Alliance, Stanford University, Stanford, CA, USA. odayj@stanford.edu.
Sarah C JohnsonWu Tsai Human Performance Alliance, Stanford University, Stanford, CA, USA.
Jeongeun KimWHOOP Inc., Boston, MA, USA.
Summer R JasinskiWHOOP Inc., Boston, MA, USA.
Kristen E HolmesWHOOP Inc., Boston, MA, USA.
Scott L DelpWu Tsai Human Performance Alliance, Stanford University, Stanford, CA, USA.
Jennifer L HicksWu Tsai Human Performance Alliance, Stanford University, Stanford, CA, USA.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

Women on average have 450 menstrual cycles in a lifetime, but we lack a characterization of physiological biometrics across the cycle and lifespan. We analyzed 1.2 million days of data from 2596 women who logged 42,759 menstrual cycles and wore a device that collected sleep and biometric data including resting heart rate (RHR), heart rate variability, respiratory rate, skin temperature, and blood oxygen saturation level. We generated novel quantifications of daily biometrics across ages and cycle lengths, finding that cycle length is strongly associated with how much cardiorespiratory metrics vary across the cycle. We observed greater cycle variability for participants who slept 6 versus 8 hours. A within-participant natural experiment showed that decreased sleep resulted in biometric changes regardless of cycle phase (e.g., RHR increased 1.2% with a 10% decrease in weekly sleep duration). These results lay a foundation to better understand and optimize female health and performance.

Identifiers

PMID42185632
PMCPMC13482339

What OpenQuestion holds

Textmetadata
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Registered trials

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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.