Definitely keep baby things in a separate bag, it's easier that way. You can phone the hospital to ask what you will need and what they provide - for example they probably provide nappies and maternity pads but may not provide nursing pads. You might want to take your own hot/cold packs. Think about what you'll want to wear while you're there - I ended up in hospital gowns cause I had a caesar and hadn't taken enough sleepwear; this time I'm going to pack yoga pants and maternity t-shirts which can be worn both in and out of bed. Nothing's really that urgent, because if you forget stuff you can always ask your partner to go fetch it!