I think the first 8-12 weeks are the "fourth trimester" so anything goes.
BFP #1: 08/17/2012 DD1 born 05/01/2013
BFP #2: 07/31/2015 M/C 09/23/2015 (11.5 weeks)
FTM, but we'll theoretically be doing babywise. If you're interested, follow the Chronicles of a Babywise Mom blog. She makes a really important point--because sleep begets sleep, sleeping enough is more important than the baby falling asleep on their own, and you definitely need to respond if your child is hungry. I like the common sense approach she takes to babywise, so we'll aim to do that. We'll see though!