On April 2, 2026, Dublin-based femtech company IdentifyHer launched Peri — billed as the world's first wearable device purpose-built for perimenopause — and began shipping to customers following a preview at CES 2026 in January. The palm-sized sensor adheres to the upper abdomen (not a wrist or ring device) and continuously tracks hot flashes, night sweats, anxiety, sleep patterns, menstrual cycles, and activity levels. Priced at $449 with no subscription fee and FSA/HSA eligibility, Peri competes in a growing femtech hardware segment but occupies a unique niche: it's the only device designed around perimenopause specifically, with algorithms trained exclusively on data from women in the perimenopause transition.
Why It Matters
Perimenopause affects every woman who lives to middle age and typically begins 4-10 years before menopause itself — yet the phase has essentially no dedicated diagnostic or tracking infrastructure. Most women experience symptoms for years before receiving any clinical guidance, because most doctors lack objective data about their patients' hormonal transitions. Peri addresses this gap directly: by continuously tracking the biometrics that correspond to perimenopause symptoms, it can provide objective documentation of symptom patterns that helps clinicians — and the patients themselves — understand what's happening and when. The growing menopause tech market ($266B projected by 2035, per Astute Analytica) has focused heavily on post-menopausal products; devices focused on the perimenopause phase represent an underserved but demographically massive opportunity.The device was founded in 2021 by scientist Heidi Davis (CEO) and physiologist Dr. Donal O'Gorman, and it marks a meaningful departure from the existing femtech wearable landscape. Most hormone and cycle tracking devices — including the NC Band from Natural Cycles (launched January 2026) and the Symex Labs progesterone patch focused on IVF — target either pre-menopausal fertility tracking or post-menopausal management. Perimenopause — the 4-10 year transition phase typically beginning in the mid-40s — has been left largely untracked. Peri's AI algorithms are trained on data from women specifically in this transition, creating what the company describes as "the first large-scale dataset on perimenopause" which it intends to use for clinical research partnerships as well as consumer applications.
The device body adheres under the breast with medical-grade patches (20 included in the kit, with replacements sold separately) and is designed for continuous wear including exercise, sleep, and showering. Two rechargeable batteries rotate so the device stays powered; the accompanying app provides weekly, monthly, and cyclical insights connecting the tracked biometrics to actionable symptom patterns. The $449 purchase price includes the sensor, two batteries, 20 patches, charger, and USB cable — no ongoing subscription is required, though the company plans to add premium analysis tiers.
Sources
- Peri Launches First Wearable Device Designed Specifically for Perimenopause — PR Newswire
- Irish femtech company Peri starts taking orders at CES — The Irish Times
- Meet Peri, the Wearable Sensor That Spots Perimenopause Symptoms Before You Do — The Flow Space
Update — 2026-04-15
Initial entry — story first created.
Update — 2026-10-16
Peri makes TIME's Best Inventions of 2026. On October 15, 2026, Peri, the Dublin company Afterglow covered at its April launch under the IdentifyHer name, said its perimenopause wearable had been named to TIME's Best Inventions of 2026 in the health & wellness category. In its announcement, Peri gives more detail on how the product was built: algorithms developed in-house over five years and trained exclusively on continuous data from 204 women going through perimenopause in human trials. The device is worn under the breast because hot-flash and night-sweat signals "dissipate toward the limbs," which the company says rules out ring and wrist devices. Peri says it is working with universities on the link between midlife symptoms and long-term cardiovascular, bone and cognitive health, and with clinics and women's health companies on research. CEO Heidi Davis: "For too long, women have gone through perimenopause flying blind."
What changed: Six months after launch, Peri has mainstream recognition and a disclosed training-set size. The figure of 204 is small for a product that promises to show clinicians "whether a treatment like hormone therapy is working, at what dose." It is the number to watch as Peri moves toward clinical partnerships, especially now that ACOG (October 15) and ACP (October 5) have both put hormone therapy first, which creates demand for objective dose-response tracking. See time-best-inventions-2026-intimate-health for the other sexual-health products on the list.