I currently have a 3 week old baby girl, born Oct. 24th... but I also have a 2 year old girl, a 17 year old son, an 18 year old son, and a 20 year old daughter! I got each one of them sleeping through the night by a month and a half. If you wish for this to happen, follow what I'm telling you! :)
At night, let her sleep, and wake up and eat when she wants. The catch: at night feedings/changings, do NOT entertain her, talk to her, make smiley interesting faces, nothing. You want her to be bored at night, not want to wake up. On the other hand, try to keep her awake when she does wake up during the day. Make the room bright, let there be noises, even if she's asleep treat her like she's awake! At every daytime feed/change, talk to her, give her things to look at and engulf her in daytime activity. If she doesn't wake every 3 hours, try to wake her up, sure, that's a good idea. I find that if I take my sleeping butterball and change her diaper when she's asleep, she usually will wake right up. Then I talk to her and suddenly she's rooting for food again. In no time, your girlie will be choosing not to wake up at night, because it's boring!!! And this has worked like clockwork for me with my past 4 kids! This one only wakes up ONCE a night, and will go right back to sleep without fuss ALREADY. She's already getting it thru her head that nighttime is not the RIGHT time for fun and games! I would bet my life savings too, that she'll also be sleeping thru the night completely before the new year. She's already did it TWICE! Good luck, and trust me, try this technique out, and be PERSISTANT, and you will be a happy camper, sleeping your nights through! Incidentally, I am breastfeeding this baby. During the day, I feed her about every 2-3 hours when she "asks" for it, or at about 3 hours I'll just stick a boob in her mouth whether or not she's asking, she never declines LOL...just so she doesn't get a little tummy ache from being hungry. If you're bottle feeding you don't have to feed them as often, more like every 3-4 hours. When they're FIRST born, I'd say, the first week or so, it's probably not the best to allow them to sleep all night without feeding... but they normally don't sleep all night anyway so there's not much of a chance of that LOL My first 3 kids I bottle-fed formula, and my 2 year old and this baby I'm breastfeeding. There's no difference with them wanting more or less sleep at this point, I've found. Gina was sleeping thru the night by 1 1/2 months even though I breastfed her exclusively. And this one's only waking up once a night now, it's SWEET, I tell ya! LOL