My midwife reminded me to do it as my "homework" between my 27 and 31 week visits. I did it much later last time around, week 35ish, but it makes sense to get it over with - in case something happens, and so you don't forget and have to do all that paperwork while in labor.
My hospital actually called me today to pre register. I'm a ftm and didn't even know you do that lol. It was a very nice surprise. I'm due next week :-)
My hospital says 30 days before your due date
My hospital has online pre-registration. It will cut down on paperwork when you get to the hospital. See if your hospital has a website. I am 32 weeks but I registered two weeks ago.
Im pregnant with my 3rd and have never registered with my hospital or was even told I had to. Thats in CA and AZ so not sure about every state.
Some hospital don't even do pre registration. My hospital says to just go in when you're in labor. So I think giving the hospital a call would be a good idea, they'll let you know when and if you can.