Prospective observational study evaluating the safety and accuracy of Feminai 1.0, an at-home adhesive patch that measures skin temperature and electrical impedance to map each breast. Up to 300 women (ages 25-75) undergoing screening will have one study visit; Feminai results will be compared with mammography and, when available, biopsy to assess sensitivity and negative predictive value. Feminai is investigational, intended to support clinical decision-making, and does not replace standard diagnostic tests.

This study will evaluate Feminai 1.0, a home breast examination kit that uses skin-surface temperature and electrical impedance measurements to create a "map" of each breast. The goal is to learn whether Feminai can help identify the presence or absence of suspicious soft-tissue lesions that may need further medical evaluation. The device is intended to support clinical decision-making and is not a stand-alone diagnostic test.

Who can join:

Women ages 25-75 who are undergoing breast cancer screening. Two groups will be enrolled:

• About 150 women whose most recent screening mammogram was read as low concern (similar to BI-RADS 1-2).
• About 150 women who are scheduled for a biopsy after a mammogram that showed higher concern (similar to BI-RADS 4-5).

Key exclusions include current treatment for breast cancer, pregnancy or breastfeeding, metal implants, recent breast surgery (within 1 year), breast implants/injections, cup size larger than US size E, and any condition that would make participation unsafe or impractical.

What participation involves:

This is a prospective, observational study with one visit. After informed consent and eligibility confirmation, trained staff will apply the Feminai patch in a private room to collect measurements from each breast. Participants will complete a short questionnaire about their experience. Routine clinical care (such as mammography and, if planned, biopsy) will occur as usual; there is no randomization and no change to standard care. To avoid anxiety or influencing medical decisions, Feminai results will not be shared with participants or their physicians.

Risks and discomforts:

Expected risks are minor and temporary, similar to other adhesive skin patches: mild skin redness or irritation, itching, slight discomfort when the patch is removed, brief indentation marks, or mild dryness/sensitivity, especially with repeated applications. Serious device-related risks are not expected but will be monitored. Any device malfunctions will be recorded.

Inclusion Criteria:

General:

1. Females aged 25-75 years.
2. Able to comply with study procedures and follow-up requirements.
3. Willing and able to provide informed consent.

Additional for Group 1 (up to N=150):

1. Presenting for routine mammography/tomosynthesis breast cancer screening according to national/regional guidelines.
2. Most recent mammography result - BIRADS 1 or 2

Additional for Group 2 (up to N=150):

1. Presenting for biopsy following BIRADS 4-5 mammogram

Exclusion Criteria:

1. History of current treatment for breast cancer.
2. Pregnancy or lactation.
3. Presence of any implanted metal.
4. Any condition that, in the opinion of the investigator, may interfere with the participant's ability to comply with study requirements or may pose a risk to the participant.
5. Has breast enhancements (e.g. implants or injections)
6. Subjects who have undergone surgery (e.g. lumpectomy or mastectomy) in the last year at the time of study enrollment
7. No subject will be allowed to enroll in this trial more than once.
8. Cup size larger than E in US-based sizing charts.

Female

Women between the ages 25-75 undergoing breast cancer screening