What type of birth control? Progesterone only or estrogen and progesterone? You don't get a real period on the estrogen based pills, you get withdrawal bleeding. With those, it would just be an indication that the hormones don't drop to a low enough level for you to have withdrawal bleeding.
Otherwise, if it is the nursing, I have heard of lots of people who have gone for 2 years and longer with nursing and the average being 14 months. For me, mine came back at 5.5 months PP, but my cycle is A LOT longer than it used to me.
Finally, just because you haven't had a period doesn't mean you wouldn't be fertile. If you are interested in having another child, I would ditch the pills and see what happens. Your cycle will eventually return.