Some doctors/ultrasound techs, will make you undress and put on a gown, others will just have you slide your pants down to your hips and pull your shirt up. All depends on the nurse/tech, whichever their preference. If your wife is uncomfortable with being undressed, she should express her concerns to them and im sure they would do what that had to-to make her comfortable. As for the transvaginal ultrasound, she would have to be undressed from the waist down for that.

Is your wife pregnant?

No, just the doctor being cautious now that she's turned 40. Yes they did have her undress completely, and yes they did both the transabdominal and the transvaginal.

She shouldn't have undressed completely. That seems weird to me. I have had a transvag. When I was 20 weeks, and it was like a pap...Undressed from the wasit down and they gave me a sheet, so I wouldn't feel so exposed.

There was a radiologist, and a tech. They were great, and made me feel comfortable.
They then left the room., let me get dressed, and came back in for the normal belly one, which I just pulled my shirt up.
The transvaginal one was to get a better look at my cervix, and birth canal. They were worried I wouldn't be able to deliver natural, because I am petite... But I did, and he was almost 10 pounds.