SMS mass notification, is it possible?

The wife and I are expecting and rather than spending the first half of her labor phoning everyone, or the first bit of the baby’s life phoning everyone re: the birth, etc, I would much rather send a quick SMS to a service that then sends it on to a group of people that I have predefined.

I do plan on setting the GrandCentral voice mail to keep people updated on the baby, but for the beginning of labor and when the baby arrives, I need to send out a quick message.

Does something like this exist? I was looking at Pinger (www.pinger.com), but I am looking for other services.