Hypothetical pregnancy talk ahead, use caution if you need it.

As some of you might know from previous posts, my husband and I are planning to start a family, possibly next year. We had a discussion a few weeks ago about when we would tell our family, friends, coworkers, boss, et cetera, about impending parenthood. I'm inclined to tell immediate family and super-close friends right away, but ask that they wait until the second trimester to tell people. Of course, this means we have to rely on them to not spread the word instantly, which will be difficult.

Originally I wanted to wait until 12 weeks to tell anyone, then my husband pointed out just how bad I am at keeping secrets. He also doesn't think it's fair to tell his parents great news, and ask them not to talk about it for 2-4 weeks, but that they'd be hurt we didn't tell them sooner if we wait til 12 weeks.

For those of you who have been through this, what did you do?

Update: Thanks for all the advice. The idea of only telling people that I would want to know about a miscarriage or other termination is a good way to look at it.