Why not make a label with something like:
Especially for _____________________________
Born ____________________ at _______________(for time)
Length _____________________________________
Weight _____________________________________
Made with love by...
You could put some other sentiment (i.e. "Our little bundle of joy" "Our blessing from above" etc.)
Use a perma pen to fill in the blanks after the baby is born.
Another idea would be to complete the quilt and add the label later.