How early can u see a pregnancy on xray/ultra sound?

Vaginal u/s?: You can see a pregnancy with a heartbeat on vaginal ultrasound at 6 weeks. You can see a sac a week early. We don't use x-rays to look a early pregnancy.

About 6-7 weeks : Depending on the first day of your last period usually we see a pregnancy around 6-7 weeks (we see a thickening of the uterus lining first around 4 weeks, then a sac with fluid with a little dot (fetal pole) around 5 weeks. If we look with a transvaginal ultrasound we see it around 6-7 (with heartbeat). If you are not sure about dates we do a bhcg; 1500 transvaginal, 2500 abdominal ultrasound.