According to a first aspect of the invention, there is provided a device for estimation of an ovulation date, comprising a camera, configured to obtain colour data of successive FSH test strips and a processor, configured to evaluate the colour data obtained by the camera. The processor is configured to determine a concentration value of each successive FSH test strip based on the data of the camera and to output a signal, if the processor determines that a first FSH downward trend of the FSH test strip values is occurring in the successive FSH test strips.
