Aim:
To evaluate the effectiveness of determining the fertile window in women with idiopathic infertility based on the results of crystallization of saliva samples obtained using the Ovul portable device with a mobile application by comparing them with the results of urine test strips and folliculometry data.

Material and methods:
The menstrual cycles of 42 women with idiopathic infertility were analyzed: Group I - 21 women who took drugs to induce ovulation, Group II - 21 women with natural menstrual and ovarian cycles. Ovulation was confirmed or excluded based on the results of the Ovul device, urine test strips, and folliculometry.

Results:
Although ovulation detection using the Ovul device and urine test strips has 100% specificity, the sensitivity of the device is 97.4%and the accuracy is 97.6% (if the positive result is ovulation or the fertile window), while for urine test strips the sensitivity is 94.9% and the accuracy is 95.2% if we consider a positive result not only to be the same as the day of ovulation according to folliculometry, but also a positive result within the next 72 hours (mainly 12-24).

Conclusions:
Ovulation detection using the Ovul device is a highly accurate, 100% specific and highly sensitive method that can be used at home, will optimize diagnostics, make it more convenient and cheaper for patients who want to get pregnant or, on the contrary, who are trying to avoid pregnancy.