In our time for a reliable determination of ovulation doctors perform repeated ultrasound monitoring, which allows you to evaluate the development of follicles and ovulation. Ultrasound monitoring allows: to assess the overall state of the uterus and ovaries and their compliance phase of the cycle; oversee the development predict the approximate timing of approaching ovulation and confirm ovulation has occurred; observe the growth of the endometrium during cycle, which allows to detect some violations; identify violations of ovulation; for irregular cycles and hormonal disorders helps to clarify the reasons for the delay and decide on appropriate treatment. When correct approach when the first ultrasound is done as close to the estimated ovulation day is enough to conduct ultrasound twofold per cycle, in extreme cases – three times since size dominatnogo follicle defined on the first study, we can calculate the approximate time of ovulation, given the average growth rate of follicles 2 mm / day. At this time ultrasound monitoring was nabolee informative, reliable and economical than all other methods of determining ovulation. We should also mention the psychological aspect of ultrasound (assuming the patient explanations, which means that the obtained picture). In the case with all of the other methods of diagnosis, if they do not pokayvayut ovulation, the patient remains in the dark – no ovulation at all ever, and it is fruitless, or no ovulation in this cycle and will not, and no hope or no ovulation yet, but tomorrow it maybe. With ultrasound monitoring can predict the presumptive term of ovulation, and not simply conclude that today it is not.