Our ultrasound guy just says "baby" for everything - "there's baby's stomach" or "here's baby's arm" etc.
He actually seemed disappointed when we told him we weren't finding out, I think he was looking forward to it He asked twice, the first time as "was there anything else you wanted me to look at?" then straight out "are we finding out the sex today?"

Now, here's hoping when we have our 30 week u/s we don't have a slip up! ("Baby" has a cyst in his/her brain, we have to check if it's grown, gone away, or stayed the same size at 30 weeks )