I always planned to get pregnant before 30 due to statistics. According to my preggo guide, a woman between 25-29 has a 86-93% likelihood of getting preggo within a year of trying. It took us one month. I'd like to have one more (on good days anyway), probably when I'm about 32 or 33. According to the same data, my likelihood within one year is 72-86%. Not too shabby.
But even the late 30s have a 65%-72% chance! It's hardly impossible.