The use of ovulation test paper to monitor ovulation has been in the case of a bar is likely to be due to the following reasons: 1, there is no ovulation, so ovulation test paper will not appear strong positive results, it is recommended that you can monitor ovulation through ultrasound on the twelfth day of the menstrual period, and respectively, in the menstrual period of the fourteenth and sixteenth days to do ultrasound, mainly to understand the follicle whether the normal development of the menstrual period in the first 16 days whether it has ruptured and discharged an egg. The main purpose is to know whether the follicle has developed normally and whether the egg has been ruptured and discharged on the 16th day of menstruation, so that you can know whether there is ovulation or not under the visualization.2. If there is no ovulation through ultrasound monitoring, it is recommended to check the sex hormone six test, according to the results of the sex hormone six test to understand the function of the ovary, and to understand the situation of estradiol, and then decide whether it is possible to stimulate ovulation treatment.