That didn't even occur to me but her CPM status may be why. That was not the reason I was giving for denial of coverage, though. The radiology clinic is independent but the ultrasound techs are hospital employees, they had no problem doing my ultrasound with my midwife's script and had worked with her a lot in the past. I was shocked when I got the letter and actually showed my pregnant neighbor and she was just as shocked because she had already had 3 ultrasounds by that point and was expecting at least one more, and Tricare had covered all of them.
My 20 week ultrasound actually happened at 26 weeks because I wasn't in a hurry to get it done, but my midwife just wanted to make sure everything was where it was supposed to be. That could be why they wouldn't cover it as well, but online is clearly states that they will cover ultrasounds for certain criteria regardless of stage of pregnancy.
This is was Tricare says about it: http://www.tricare.mil/mybenefit/jsp...re&topic=Women
I would think evaluating fetal growth would meet criteria for the anatomy scan.