Phira Launches With Earring-Back Wearable That Tracks Hormones in Real-Time

Founded by Dr. Alisha Menon, Ph.D. in Electrical Engineering & Computer Science from UC Berkeley, Phira today emerged from stealth with the first results on wearable hormone tracking, announcing early findings from its “invisible wearable”, a discreet non-invasive earring-back wearable that aims to make hormones as accessible as heart rate or sleep. The pilot study identified novel biomarkers consistent with estrogen, LH, and progesterone dynamics across the menstrual cycle. The company plans to launch commercially in 2027 and is opening its waitlist for early access.

What Phira is
Phira is a wearable built into an earring-back that continuously and non-invasively measures biosignal patterns behind the ear, enabling real-time tracking of estrogen, LH, and progesterone dynamics across the cycle. Designed to disappear, the wearable discreetly collects data 24/7 and delivers personalized insights each morning into the wearer’s hormones, cycle progression, fertility, and overall well-being. The wearable is compatible with most earrings, comfortable to sleep in, waterproof, and built for multi-week battery life.

Current and emerging wearables, including those positioned as hormone trackers, only estimate cycle phase from signals like wrist or finger temperature, heart rate, heart rate variability, and historical cycle data, without providing insight into the underlying hormone dynamics driving each cycle. Other emerging technologies pursue direct biochemical sensing through interstitial fluid or other biofluids but face substantial reliability challenges outside the lab. Phira follows a different path. Built on decades of peer-reviewed scientific literature linking reproductive hormones to the body’s thermoregulation, Phira continuously measures high-resolution physiology from the posterior ear, a sensing location with stronger coupling to core body signals than extremities like the wrist or finger.

In an IRB-approved pilot study, with foundational findings peer-reviewed for a leading IEEE conference, Phira became the first to surface evidence that a wearable can track estrogen, LH, and progesterone in real-time. These findings represent the first demonstration that continuous wearable sensing can reveal hormone patterns in real time, marking a fundamental shift from estimating cycle phase to observing the underlying hormone physiology that moves with it. An expanded study is now underway to validate the technology across a larger population, including women diagnosed with PCOS/PMOS or in perimenopause.

Why it matters
Reproductive hormones influence nearly every aspect of female physiology, from energy, mood, and sleep to fertility, menopause and long-term health, yet an estimated one in two women will experience hormonal imbalance in their lifetime, one in four struggle with irregular cycles, and one in eight face conditions such as PCOS/PMOS. These imbalances are linked to longer-term risks including cardiovascular disease, diabetes, infertility, and earlier cognitive decline. Still, hormonal health remains one of the least accessible areas of personal health data, relying on intermittent lab tests, impractical daily urine assays, or wearables that only estimate cycle phase, leaving women without real-time insight into the hormones driving their health and fertility.