System and method for unobtrusively determining a fertile window

1. A system for determining a fertile window of a woman, the system comprising:

a contact sensor unit in contact with the woman, wherein the contact sensor unit includes a CO2 sensor and is configured to provide a signal indicative of respiration of the woman; and

a processing unit configured to process the signal to obtain a biomechanical parameter indicative of the respiration, and determine the fertile window of the woman based on changes in the biomechanical parameter,

wherein the biomechanical parameter includes at least one of a minute volume, a respiratory drive and thorax expansion.

2. The system according to claim 1 , wherein the biomechanical parameter is indicative of hyperventilation.

3. The system according to claim 1 , wherein the contact sensor unit is integrated in a wrist-worn device.

4. The system according to claim 1 , further comprising a communication unit for notifying of at least one of whether the woman is in the fertile window, when the fertile window will be, and at least one of when ovulation will take place and when menstruation will take place.

5. The system according to claim 1 , further comprising a storing unit for storing at least one of the signal and the biomechanical parameter.

6. The system according to claim 1 , further comprising a user input unit for receiving user input on signs related to menstrual cycle of the woman, wherein the processing unit is configured to personalize determination of the fertile window during a learning phase based on the user input.

7. The system according to claim 1 , further comprising an activity determination unit for determining an activity of the woman, wherein the processing unit is configured to relate the biomechanical parameter indicative of respiration to the determined activity.

8. The system according to claim 1 , wherein the CO2 sensor is configured to non-invasively estimate a CO2 concentration of arterial blood of the woman, and wherein the CO2 sensor comprises at least one of a potentiometric sensor and an optical CO2 sensor.

9. The system according to claim 1 , wherein the processing unit is configured to determine a beginning of the fertile window of the woman based on an increase of the minute volume, and the respiratory drive.

10. The system according to claim 1 , wherein the contact sensor unit comprises at least one of:

a bio-impedance sensor configured to be attached to a thorax of the woman, wherein the bio-impedance sensor is configured to obtain a signal indicative of a tidal volume, wherein the processing unit is configured to determine the minute volume based on a product of the tidal volume and a respiratory rate,

an electromyography sensor configured to determine an electrical activity of intercostal parasternal muscles, wherein the processing unit is configured to determine the respiratory drive from the determined electrical activity, and

at least one of an inductance and a stretch sensor for measuring an expansion of the thorax of the woman, wherein the processing unit is configured to determine the respiration rate based on the measured expansion of the thorax.

11. The system according to claim 1 , wherein the contact sensor unit is directly integrated into a bra to contact a skin of the woman.

12. The system according to claim 1 , wherein the CO2 sensor is configured to non-invasively estimate a CO2 concentration of arterial blood of the woman, and wherein the processing unit is configured to determine a beginning of the fertile window of the woman based on an increase of the minute volume and the respiratory drive.

13. A method for determining a fertile window of a woman, the method comprising acts of:

providing a signal from contact sensor in contact with the woman, wherein the signal is indicative of respiration of the woman, and wherein the contact sensor includes a CO2 sensor;

processing the signal to obtain a biomechanical parameter indicative of the respiration; and

determining the fertile window of the woman based on a change in the obtained biomechanical parameter,

wherein the biomechanical parameter includes at least one of a minute volume, a respiratory drive and thorax expansion.

14. A non-transitory computer readable medium comprising computer instructions which, when executed by a processor, configure the processor to cause performance the acts of the method of claim 13 .

15. A system for determining a fertile window of a woman, the system comprising:

a CO2 sensor configured to provide a signal indicative of a respiration of the woman; and

a processor configured to:

process the signal to obtain a biomechanical parameter indicative of the respiration, and

determine the fertile window of the woman based on a change in the obtained biomechanical parameter,

wherein the biomechanical parameter includes at least one of a minute volume, a respiratory drive and thorax expansion.

16. The system according to claim 15 , wherein the sensor is a contact sensor configured to contacts a skin of the woman.