Baptism invitations, a discussion.
You know that is really not the proper way to do it though. Anyway, you probably do not have all the people you want to let know about the baby on your cell phone calling list. Sending out traditional formal baby announcements is still the best way to let everyone know about the new baby. You will find that more people are apt to send a baby gift if you send them a traditional baby announcement. People just do not respond to text messages and emails the way they do paper mail.