I would wait - had too many friends lose a baby in the last tri-mester and it seemed to happen as I was working on a quilt. Back then I would embroider the quilt blocks by hand then make the quilt so it took a while. But after the second time I decided to wait. It was less stressful. And as my niece found out, the ultrasounds are not always correct. She was supposed to be having twin boys and the first one born was a little girl. Another friend of mine was told her son had a terrible tumor that would need immediate surgery, so they scheduled a c-section, and the "tumor" was his little sister. I won't go on - but there have been many like that. Not to mention, one friend took one look of their new baby and changed the planned name. So some times they are right on and sometime not.