> For the complete documentation index, see [llms.txt](https://docs.tryterra.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.tryterra.co/faq/help-topics/data-api-sdk/provider-coverage-and-per-provider-data-availability/garmin-historical-menstruation-via-api-pull.md).

# How do I get historic Garmin menstrual cycles?

Historical menstruation data from Garmin is retrieved the same way as any other historical data: via the [historical data-retrieval endpoints](https://docs.tryterra.co/health-and-fitness-api/managing-user-health-data/requesting-historical-data).

* **Call `GET /v2/menstruation` with a `start_date`** set far enough back to cover the oldest cycle you need, and `to_webhook=true`. The range must span the period start date of that cycle.
* This triggers Garmin's backfill, which Terra delivers asynchronously to your destination. Garmin allows up to **5 years** back, subject to Garmin's own backfill limits.

Note that the initial connection backfill alone may only return roughly one recent cycle, so an explicit request with a wider `start_date` is what surfaces older cycles.


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