You can do transvaginal ultrasound after intercourse to check whether there is ovulation, because when doing vaginal ultrasound, the ultrasound probe will be covered with a disposable condom safe and hygienic, and there is no effect on fertilization and pregnancy. Ovulation monitoring is a dynamic and regular monitoring process, relying on a single or near-ovulation check, may not always be able to check for ovulation, usually around the 10th day of the menstrual cycle to do ultrasound to check the size of the follicle growth, according to the results of the measurement and then decide the next review time. Ovulation occurs on the 14th day before the next menstrual period. If you have been monitoring, and this time you are simply determining if the follicle has been expelled, you can do the ultrasound only once.