I've only packed a hospital bag once, for my first, and that was over 15 years ago! Can't remember what I put in it. My second and fourth came under circumstances we weren't prepared for and the third was a homebirth so this is what I've packed for this birth.
In case I need to stay overnight rather than have an ambulant birth:
Nursing tanks and warm, button up shirts
comfortable kuschelhose
warm socks
slip on shoes (in my case, crocs knock-offs)
underwear
tooth brush/paste/personal toiletries
comb/hair elastics
hand mirror
Handy charger
ear plugs!
For the birth:
camera
hand breastpump (should baby not be able to nurse within the first hour)
Baby's going home outfit (this one is traditional--all my babies have worn this outfit home except, of course, my homebirthd baby)
Fleece snowsuit for baby (Still need to get one, though. I like the one from Jako-o but I'm not spending that kind of money!)
Mutterpass with my note to the Hebammen about my particular wishes
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