How to surprise fiancé with gender results?

Monet
My fiancé was in a previous marriage and it took them 14 years to conceive two girls. Now our gender ultrasound is coming up on our 2nd year anniversary. (Yeah I did a little thinking  on that part lol) so in my mind I'm going to tell the nurse to tell the dr. Not to say anything about the gender (obviously because my honey will be there) and say he couldn't see or the baby's legs were closed and when he leaves the room he tells the nurse and she will write it down and give it to me as I'm leaving. I planned on later in the evening since it's our anniversary letting that be his gift because he is over the moon I just need ideas on how to do it. Put it in a card? Blurt it out ? Help hahaha thanks a lot