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Belle Ring  /  Endometriosis
1 in 10 women

Your body has been telling the story all along.

Endo pain has a pattern — temperature drift, sleep fracture, HRV crash. Belle Ring quietly maps the physiology underneath your symptoms, day after day, so the picture stops being one you have to remember.

Pre-order — €299 Take the endometriosis self-test
Léa · 27 · 3 cycles tracked
Pain log · body temperature
What Belle Ring sees

The earliest tells, before they fully show.

Endometriosis shows up in physiology long before the worst symptoms peak. Here are a few of the signals — yours may look slightly different — that Belle Ring keeps an eye on.

01

Pain timeline

Log pain in 5 seconds — location, severity, what you took. Each entry stamps onto your cycle, your temp, your sleep.

−47% logging time vs apps
02

HRV crashes

Endo flares show up in HRV before pain hits. We surface the early dip so you can adjust before the day collapses.

12hrs avg early warning
03

Sleep × pain

The nights before a bad day are the loudest signal. Wake-after-sleep-onset and fragmentation rise before symptoms peak.

3 nights pre-flare window
Made to be heard.

From "pain that's hard to describe" to a pattern your provider can act on.

Endometriosis takes, on average, seven years to diagnose. Most of that delay isn't medicine — it's translation. Belle Ring logs your flares passively, watches body temperature and HRV overnight, and maps every entry to where you are in the cycle. Over a few months, the pattern your gyn needs to see assembles itself — quietly, in the background, in your own data.

What you see Three cycles in one glance — and the pattern stops being invisible.
Léa · 27 · 8-year delayed dx

"For years I thought I was just bad at being a person on certain days. Now I can see my body has a shape — the same days bring the same kind of pain, the bad weeks line up, the sleep collapses before the worst of it. I finally understand what's actually happening to me."

Endometriosis-specific questions
Will Belle Ring diagnose endometriosis?
No, only a specialist can — endometriosis diagnosis still relies on laparoscopy or imaging combined with clinical assessment. What Belle Ring offers along the way is steady, passive documentation: continuous body temperature, HRV, sleep architecture and your own pain logs, all mapped to where you are in the cycle. Over weeks, that record turns the ambient "I just don't feel right" into something you can describe with dates, days and trends — language that's easier to work with, for you and for whoever is helping you.
I'm post-surgery / post-ablation. Useful?
Yes — possibly more than pre-surgery. Tracking recovery, monitoring for recurrence, and seeing whether HRT or hormonal suppression is actually quieting things down all become measurable.
Does it work with an IUD?
Yes. Hormonal IUDs (Mirena, Kyleena) often suppress ovulation; the app switches to a non-cycle view and tracks pain, HRV, sleep, and inflammation markers without forcing a 28-day rhythm.
Can I track endo with adenomyosis?
Yes — both are tracked together. Many users have both, and the app shows their distinct signatures side-by-side.
What about pelvic pain that isn't endo?
Belle Ring tracks the pattern, not the cause. If your pain has a different origin — interstitial cystitis, vulvodynia, pelvic floor dysfunction — the cycle alignment and physiology data still hold value, but identifying the actual cause needs a qualified clinician. Belle is a companion to that work, not a stand-in for it.

Have a question we didn't cover? Reach out to our team.

Other conditions Belle Ring is built for
PMDD → PCOS → Perimenopause & Menopause → Fertility / TTC → Pregnancy & Postpartum → Neurodivergence →
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