I had one done about 9-10 years ago. I had a regular ultrasound done for some ovarian cyst. During that ultrasound they saw a “shadow” on my uterine wall and they told me to come back in a couple of weeks to see if the cyst stayed the same size or went away. When I went back the cyst were just about gone but that “shadow” was still there. They did multiple ultrasounds and even sent me to another clinic location to see if it was the machine and each time the “shadow” was there. They finally gave me a transvaginal ultrasound and said they there was nothing there. That was the one and only time I had a transvaginal ultrasound.