Well first of all congratulations on surviving almost your first year year with your first, and congrats on your soon to be new family addition as well. That being said...I feel you. My son woke up several times a night until he was eighteen months. He ate every 1 1/2 hours the first six months of his life, and he was a lazy eater (30 plus minute bottles). My daughter will be one in three weeks, and she wakes up once a night now, when she is not teeting, to eat, usually around 2:30 - 3:30 a.m. I just figure she hasn't eaten for 7 or 8 hours by that ppoint, of course she's hungry...wouldn'y you be too... (fortunately she eats quickly, 5, 10 minutes tops. I'd be willing to bet as his activity level increases he will sleep longer, also have you tried some little toys he can play with, just for him. Do you rush right in? I know I rushed right in wioth my first too. Hang in there, you will all sleep eventually..beside, your hubby could wake up to feed him too, especially since your pregnant right now.
P.S. Also remember, sleeping through the night means seven or eight hours, not twelve.