After two kids in which I was with my wife for all of the ultrasounds, they never mentioned any thing about possible harm to the baby. No forms to sign. Nothing.
In fact, my wife had about triple the amount of ultrasounds done during each pregnancy due to complications.
Ditto and it makes for an interesting start to the baby album, doesn't it? I suppose that hourly viewing or for that matter viewing for an hour is a whole different issue than even a once-a-week regime for a problem pregnancy. That might explain why we didn't face a mountain of paperwork.