PRE Birth Announcements AKA Pregnancy Announcements

I really am not sure what you call these, but I wanted to come up with a clever way to tell our families that we are expecting another child. With our daughter, we lived near my husband's family so we were able to tell them all in person. And we called all of my family to tell them. Now, we don't live near any of our family and the prospect of trying to decide whom to call first, and when we would have time to call up to 10 people to tell them, was a bit daunting. I have a book by Danny Seo, "The Green Martha Stewart" called Simply Green Parties. I read it a few months back and there was a project where he used baby clothes as invitations to a baby shower. When I was at my friend's children's shop, I noticed some used preemie onesies for a few bucks a piece and had an idea... I could turn them into pregnancy announcements, mail them all on the same day, sit back and wait for people to start calling us. This way, since everyone lived in different areas, and had different commitments and schedules, we could expect about a call a day. What a great way to make recycled announcements out of these ultra small onesies...