Frequently Asked Questions

femSense is suitable for fertile women who bleed and ovulate. If your cycle is between 21 and 35 days and the cycles do not differ more than +/- 3 days: femSense is for you!
If your menstrual cycle is irregular, then femSense cannot reliably predict your fertile window. In this case we recommend that you consult a doctor before choosing femSense.

The femSense System consists of a very precise temperature sensor embedded in an adhesive patch and the supporting app.

The sensor patch is worn underneath your arm.Once activated the patch measures the body temperature continuously, 24/7, for up to 7 days.To work correctly the patch should be read by your NFC capable smart device at least once (1) a day. The app will ask you to read the patch twice (2) a day for optimal evaluation.femSense tells you when you are fertile and, based on the recorded temperature data, femSense can detect and confirm ovulation.Every month the app reminds you when to apply the patch, when to read the patch, and when you are fertile.

femSense reliably detects your ovulation and most fertile days using continuous temperature measurement and the well-known temperature method.
Based on your previous periods the femSense app can predict your fertile window, the days you are most likely to get pregnant. The femSense sensor patch measures your body temperature continuously, 24/7 during your fertile window to measure and confirm your ovulation. You are fertile in the days shortly before and immediately after ovulation.

The temperature sensor used in the femSense patches detects temperature differences smaller than 0.1°C and was especially designed to detect the postovulatory temperature rise, which is typically between 0.2°C-0.5°C.
In contrast to the basic basal temperature measurement method, the patch records a temperature value several times per hour. As the patch is always in the same position, measurement artifacts can be minimized.  A clinical study with the medical university in Graz proved the accuracy of the sensor patch and now an independent Swiss statistics institute has confirmed that femSense is 99.73% accurate when predicting ovulation.

You can use one patch per cycle. After applying and activating a patch according to the in-app instructions, the patch is associated with your current cycle.

Of course, you can shower while wearing the patch. The patch is designed in such a way that daily body care is possible. However, long baths and sauna sessions should be avoided, as the warm environment can reduce the adhesive strength of the patch (as with any other skin patch), which could cause it to peel off prematurely.

The femSense Patch is made of hypoallergenic materials used in medical wound care. However, some people with very sensitive skin may still react to the patch or the adhesive. Symptoms such as itching, burning, redness or slight skin swelling may occur. In this case please remove the patch and apply a soothing ointment to the area.If you are unsure whether femSense is suitable for you, please contact your doctor or get in touch with our technical support via e-mail to: customercare@femsenseus.com.

Of course, but as with any common bandaid, adhesiveness may be impacted depending on the amount and exposure to sweat/water/heat. Having said that, the tech inside the patch won't be impacted at all.

Each box contains 1 femSense patch.

Certain medical conditions do not allow femSense to reliably measure ovulation. These include:

• Serious, acute or chronic diseases
• Nicotine or alcohol abuse
• Amenorrhea Oligomenorrhea (too infrequent menstrual bleeding)
• Polycystic ovary syndrome (PCOS)
• Obesity (BMI > 30)
• Hirsutism
• Known allergy to components of plasters or adhesive Medication that can influence your body temperature
• Hormone treatments (e.g. pill, hormone injections, IUD, etc.) may affect body temperature

Extreme weight conditions can affect the reliability of femSense. If you are not sure whether femSense is suitable for you, please consult your doctor before beginning use.