You're talking about a Norplant. It's like coming off the pill, so it's best to wait at least a month or so to allow your body time to clear itself of hormones and get on track with your cycle. I had one years ago and it really messes up your periods, either through none at all or excessive bleeding. Of course, I was one of the lucky ones (not) and bled like every day!
That's one reason I wanted it out. Anyway, I think I got pregnant about three months after having it removed. You should ask the doctor when you're getting it removed how long it's best to wait before trying to conceive.
