Women's cardiac health
is the missing piece.

Meet longitudinal clinical-grade heart monitoring designed for the bra women already wear.

For Clinicians → Join the Waitlist →
How We Got Here

Women were excluded from cardiovascular research until 1993, and remain underrepresented today.

Heart disease is the leading cause of death in women, yet screening often starts too late. Baseline cardiovascular screening should begin at or before age 45, during the critical perimenopause transition when intervention is most effective.

Models shaping future care are trained on incomplete data missing women, obscuring sex-specific risk and treatment response. We are building the missing piece.

Only 1 in 1,000 clinical trials focus on menopause.

Menopause Society, 2022

60% of women will have a cardiovascular disease by 2050 (AHA, 2026)

WEF · 2024

0 major foundation models trained on hormonal or cycle data.

Audit · Stanford HAI, 2025
The Source

How our breasts can help

The inframammary position is the most information-rich location in the body for continuous cardiovascular and hormonal monitoring. It's the foundation of everything Braave measures.

Anatomical diagram showing heart proximity to the inframammary position

Hormonal Sensitivity

A direct window into cycle-driven dynamics that shape cardiovascular risk.

No Fat Interference

Bypasses subcutaneous fat for a cleaner signal and lower noise floor.

Cardiac Proximity

The inframammary fold sits directly above the cardiac apex, closer than any other wearable.

The Sensor

Meet the Underfit™. The missing data, surfaced seamlessly, every day.

Seamless by design, the Underfit is a clinical-grade biosensing interface capturing 45+ sex-specific cardiovascular biomarkers from the inframammary fold, where the undercurve of the breast meets the chest wall.

Underfit bra integration
Underfit sensor detail
Underfit on body

Invisible, everyday.

  • Seamlessly integrated in the left bra cup
  • Intimate sensing without bulk or invasiveness
  • Washable, soft, designed for the female physiology

Reads where the signal is the richest.

  • Clinical-grade accuracy monolead ECG
  • Fewer signal confounders than wrist or finger placements
  • Patterns and trends clinically actionable

Privacy, always.

  • Wearers choose to share their data with research that matters to them
  • The wearer owns the data and decides when to opt in
  • Currently, only 4% of research funding goes to female-specific health. This data helps shift that.
The Data

The data research has been missing for decades.

Population cycle, E2 & Prog
Inferred
Median ± IQR (25–75th pct), relative units (0–100), aligned to ovulation day, regular ovulatory cycles only (n = 28,114)
100 75 50 25 0
ovulation
-14-70+7+14
E2 Prog
HRT vs no HRT, symptom severity
Peri + post-menopausal cohort, severity index 0–100, since enrollment
100 75 50 25 0
Mo 1Mo 3Mo 6Mo 9
On HRT (n=9,412) No HRT (n=14,895)
Life stage
Self-reported + inferred from cycle pattern
47,328 Total
Premenopausal 46.2% 21,850
Perimenopausal 29.6% 14,012
Postmenopausal 20.9% 9,904
Surgical / induced 3.3% 1,562
Symptom prevalence by stage
Share of women reporting ≥1/wk, last 28 days
100% 75% 50% 25% 0%
Hot
FlashesNight
SweatsSleep
DisruptionMood
SwingsBrain
FogJoint
Pain
Premeno Peri Post
Hot flashes, individual signal
Bra-detected, flashes / day, 28 days × daytime wear (7:00–21:00), single participant
10 8 6 4 2 0
Apr 1Apr 10Apr 19Apr 28
Sleep, HRV & temp deviation
Trend, normalized (0–100), single participant
100 75 50 25 0
Mar 6Mar 19Apr 2Apr 15Apr 28
Sleep HRV Temp Dev
Braave proxies, inferred hormonal trends
Inferred
Wearable-derived proxy signals, relative units (0–100), not lab values
100 75 50 25 0
Mar 5Mar 19Apr 1Apr 8Apr 22
E2 Prog FSH LH Cortisol TSH

A continuous, longitudinal dataset of women's cardiovascular and hormonal signals. Data is opt-in, de-identified, HIPAA-aligned, GDPR-ready. Built to fill the gap most health AI was trained without. Open to academic, clinical, pharma, and AI lab partnerships.

research@wearebraave.co →
The Science

Braave measures electricity & temperature for clinical-grade accuracy.

Most wearables rely on optical sensors to estimate heart rate. The Underfit™ captures the heart's direct electrical activity from the chest, alongside core temperature precise to a tenth of a degree. This medical-grade ECG tracking reveals micro-signals that shift in tandem with hormones.

For Clinicians → Join the Waitlist →

Braave is a continuous monitoring system, not a diagnostic device. Lab-validated against clinical-grade ECG with the University of Portsmouth and FDA-grade core temperature. Pursuing Class II 510(k) clearance.

How we measure hormones through ECG with clinical-grade accuracy:
QTc prolongation
QTc interval ECG waveform measured by Braave sensor

What it is: The corrected interval between heart-muscle depolarization and repolarization.

Why it matters: Even small extensions can signal hormonal shifts, and elevated cardiac risk in women that PPG sensors miss entirely.

P-wave duration
P wave ECG measurement from Braave continuous cardiac monitoring

What it is: The time it takes for the atria to depolarize.

Why it matters: Estrogen modulates atrial conduction; subtle changes here track ovulation, perimenopause, and stress with remarkable precision.

ST-segment variability
ST segment ECG analysis from Braave wearable sensor

What it is: Beat-to-beat fluctuation in the segment between ventricular depolarization and repolarization.

Why it matters: Hormonal cycles, autonomic state, and recovery all leave fingerprints here.

T-wave alternans
T wave ECG measurement captured by Braave health sensor

What it is: Microvolt-level alternations in the T-wave's shape.

Why it matters: A subclinical signal that's been linked to estrogen withdrawal, anxiety load, and elevated arrhythmia risk in female physiology.

QRS complex duration
QRS complex ECG measurement captured by Braave health sensor

What it is: The duration of ventricular depolarization — the electrical pulse that triggers each heartbeat.

Why it matters: Estrogen influences ventricular conduction speed; subtle QRS widening has been associated with perimenopause, elevated cardiovascular risk, and autonomic dysregulation in women.

ECG (electrocardiogram)
Clinical ECG measurement data from Braave continuous monitoring bra

What it is: A continuous electrical reading at ±1–2 ms timing accuracy, validated against gold-standard hospital ECG.

Why it matters: Most consumer wearables read 30-second snapshots; clinical-grade means we never stop listening.

Sensor Specifications
ECG
Clinical-grade, continuous, ±1–2 ms timing accuracy. Read at the cardiac apex.
Temp
FDA-grade core temperature, ±0.1°F precision.
Contact
5× the contact surface area of a wrist wearable.
Wear
More than 8 hrs/day. Daily-life invisible.
Hormones
Breast-sweat hormone sensing, Phase 2.
Validation
Lab-validated against gold-standard ECG and core temperature with the University of Portsmouth Breast Health Research Group.
› Biomarkers Braave Reads 43 active, 4 next generation
Cardiac · Electrical
  • Heart rate
  • RR interval
  • QTc interval
  • PR interval
  • QRS duration
  • P-wave duration
  • T-wave morphology
  • ST-segment morphology
  • AFib detection
  • Arrhythmia (PVC / PAC / SVT)
  • Fragmented QRS
  • T-wave alternans
  • QT dispersion
Autonomic · HRV
  • HRV — RMSSD
  • HRV — SDNN
  • LF / HF ratio
  • Sympatho-vagal balance 24h
  • Poincaré SD1 / SD2
  • Sample entropy
  • Baroreflex sensitivity
  • Deceleration capacity
  • Respiratory rate (EDR)
  • Cardiac output estimate
Thermal · Metabolic
  • Basal body temperature
  • Ovulation detection
  • Pre-ovulatory nadir
  • Luteal phase length
  • Circadian phase (acrophase)
  • Circadian amplitude
  • Hot flash signature
  • Fever detection
  • Thyroid function proxy
  • Thermoregulatory efficiency
  • Post-exercise recovery
Integrated · Cross-Domain
  • Menstrual cycle phase
  • Stress / cortisol proxy
  • Allostatic load score
  • Cardiorespiratory coupling
  • Thermal–HR modulation
  • Core temp – HRV coherence
  • Metabolic rate estimate
  • Inflammation proxy
  • Insulin resistance signal
Next Generation · Breast Sweat
  • Estrogen (E2)
  • Progesterone
  • Cortisol
  • Luteinizing hormone (LH)
Peer reviewed white papers
AI / Cardiology
Advancing Our Understanding of Women's Cardiovascular Health Through Digital Health and Artificial Intelligence
JACC: Advances, 2023
Endocrine
Thyroid Hormones and Electrocardiographic Parameters
PLoS ONE, 2013
Cardiology
Sex Differences in Heart: From Basics to Clinics
Physiological Research, 2023
Endocrine
Sex Hormones and the QT Interval: A Review
Journal of Women's Health, 2012
AI / Cardiology
Artificial Intelligence-Augmented Electrocardiogram in Determining Sex: Correlation with Sex Hormone Levels
Mayo Clinic Proceedings, 2023
For Clinicians

Health is what happens between appointments, not in them.

Braave provides continuous clinical-grade patient reported data measured outside of appointments and labs, integrated with the tools you already use.

Sample patient HRT response over 90 days — UI mock with embedded stats, symptom breakdown, and HRT response chart

Patient-reported data you can use in your clinical workflow.

  • Measure and track patients' symptoms with treatment.
  • Clinical-grade accuracy to a tenth of a degree.
  • Get reliable between-visit data.
Sample diagnosis suggestions dashboard — UI mock showing ICD-10 algorithm output, confidence scores, and Athena export action

Designed to integrate into your existing workflow.

  • Receive suggested ICD-10 codes based on data measured by device.
  • Get accurate between-visit context to include in clinical documentation for higher reimbursement rates.
  • Integrates with your EMR.
Privacy and security overview — UI mock showing HIPAA, GDPR, SOC 2, and AES-256 compliance with the encryption flow from device to clinic

Secure, HIPAA compliant, GDPR-ready.

  • End-to-end AES-256 encryption from sensor to EMR.
  • Data is de-identified and fully exportable.
  • Patient-owned data is revokeable and audited frequently.
  • HIPAA-aligned BAA available, SOC 2 Type II in progress.
Fall 2026 pilot: a small group of women's health clinics working with us to test Braave in real practice. Get in touch if you'd like in.
research@wearebraave.co →
How Braave Is Different

The missing infrastructure layer between devices, labs, and care.

Current tools collect fragmented signals: steps, sleep, snapshots, hormone tests. Braave is the layer that's been missing.

For Clinicians → Join the Waitlist →
Wearables At-Home Tests Cycle Apps Labs & Bloodwork Clinical Care AI & Research

Braave makes other tools smarter, advancing women's health together.

WearablesActivity, sleep, basic HR.
With Braave→Continuous clinical-grade ECG and hormonal proxies, a fuller picture of the female physiological day.
At-Home TestsSnapshot hormone readings.
With Braave→Continuous physiological context, what happened between tests, and what changed.
Cycle AppsSelf-reported cycle data.
With Braave→Objective cardiac and thermal signal, fewer manual logs, more accurate prediction.
Labs & BloodworkPeriodic bloodwork.
With Braave→The daily physiological context that explains why a value moved, and what to do next.
3,200+
Women on the waitlist
43
Active biomarkers
±1–2 ms
ECG timing accuracy
University of Portsmouth
Validated with
[TK: Dr. Advisor Name, MD]
Clinical advisor
Claire Chabaud →
Founder & CEO

It's time to put the missing pieces together. Join us.