I did a DF last night at 9:00 and she didn't wake again until 4:30! Only she woke up again at 5:40! I left her in her crib until 7:15; I could hear her cries/squeals on the monitor and she wasn't in distress. She was quiet for periods of time, and I assume she went back to sleep for some of that time--I did!
BUT...
I put her down for her first nap at 8:45 or so, about 1.5 hrs. after officially "waking." The result: 20 min. nap! OVERTIRED!!! Well, yes, of course, she'd been up since 5:45!!!
That set the tone for our naps today--crap! There were 4 of them, but they were only 20-30 minutes
I tried to extend the last one (which was probably a mistake, since she was soooo OT by then), and it led to 45 minutes of sobbing and soothing. She finally got a hold of herself, but didn't got to sleep. I left the room at 5:15, and she started to call out again; it was too late for a nap anyway, so I got her up--thankfully, she was not in a sour mood, as she'd finally regained her composure.
I have tried to extend her naps, but I got burnt out. For the most part, it doesn't work (or I give up before it does). I guess my heart's not in it. I don't know if it will make a difference. I just keep thinking/hoping that she will all of a sudden be developmentally ready and start sleeping more. (I know this is more for the naps boards, but since we're talking about it...) You say that your LO is a 45 minute napper? Does she cry upon waking? How do you know if 45 is enough?
I have also feed her more frequently today (2:45-3:15 intervals), because these weird waking might be a GS. I will do so for another day or so, if tonight shows improvement. I know FOOD is at the root of this.