Normally, a fertile woman ovulates only one egg a month. However, this is not absolute and it is possible to produce more than one egg or none at all in physiological or pathological conditions. It takes a long time for a follicle to develop into a mature follicle and then form an egg. A number of follicles develop during each menstrual cycle, but usually only one follicle matures to form an egg, which is clinically referred to as a good quality follicle. The other follicles develop to a certain point and then gradually degenerate and atrophy and become atretic. Due to physiological or pathological factors, such as stress, work pressure, endocrine disorders, polycystic ovary syndrome, injection of ovulation stimulating hormones, etc., it may result in the appearance of multiple eggs or none at all. Under normal circumstances, there is no need to monitor the ovulation situation, a long time can not get pregnant or irregular menstrual cycles need to go to the hospital in time, under the guidance of a professional doctor to carry out relevant examinations to monitor the ovulation function.