Question: When we see a patient for confirmation of pregnancy, I bill a 76817 with a dx of Z32.0-. I just want to confirm this. Someone had said I should be using 76830 instead, but I don't agree. What should I do? California Subscriber Answer: Code 76830 (Ultrasound, transvaginal) is a gynecological ultrasound, whereas 76817 (Ultrasound, pregnant uterus, real time with image documentation, transvaginal) is obstetrical. Rule: According to the CPT® Assistant, if an ultrasound is performed to evaluate pregnancy, it is always coded as an ob ultrasound even if that diagnosis is not confirmed.