Transvaginal ultrasound is a transvaginal ultrasound that can be performed on the eighth day of a woman’s menstrual cycle. Transvaginal ultrasound is what we usually call a vaginal ultrasound, and it needs to be done after the menstrual period has completely cleared. Since the uterine opening is closed on the eighth day after menstruation, transvaginal ultrasound usually does not cause infection in the uterine cavity, so transvaginal ultrasound can be performed at this time, and color ultrasound of the abdomen can be performed for women who have no history of sexual intercourse. Transvaginal ultrasound is more accurate than abdominal ultrasound, allowing early detection of lesions and assessment of ovarian function. In principle, it is more accurate to perform transvaginal ultrasound 2 to 3 days after menstruation. Therefore, women can do transvaginal ultrasound on the eighth day after menstruation.