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

What this work gives Aellic

42,759 cycles from 2,596 women across 1.2 million days: the amplitude of the cyclical swing scales with cycle length; measured across respiratory rate, resting heart rate, HRV, temperature and SpO₂. Preprint of the same work: bioRxiv, doi 10.1101/2025.09.11.675620 — the peer-reviewed version is deliberately the one cited here.

Where this sits in the engine

1 declared site: constants and thresholds in the code that point at this entry.

• Cycle Phases and cycle-aware baselines 1 site