Cycle basics · 5 minute read

Cycle tracking and health-data privacy

Questions to ask about accounts, cloud sync, exports, deletion, device security, and advertising.

Evidence-informed · Editorial review August 2026 · Links to trusted sources are available in the interactive app

Know where the record lives

A cycle diary may be stored only on a device, synced to an account, included in a backup, or shared with connected services. Each choice changes convenience and exposure.

Use available controls

Protect the device with a strong passcode, review notification previews, use multi-factor authentication where offered, and understand export and deletion options. Avoid placing identifying details in free-text notes unless needed.

Advertising and health data should stay separate

Contextual ads can be selected from the page topic without building a profile from intimate logs. Period Circle’s product direction is to keep personal cycle entries out of ad targeting and clearly explain any future data integrations before consent.

Medical disclaimer: This guide is general education, not medical advice, diagnosis, contraception, or confirmation of ovulation. Contact a qualified clinician for personal care. Call 911 for an emergency in the United States.