Maternity and Labour bags.
I would recommend, from what I've read, taking 2 bags. That way it's good too as you have your "labour" stuff in one bag so it's all easily accessible and then hospital stay/baby stuff in another.
* a clean T-shirt or front-opening nightie, dressing gown and slippers - plus bed socks if you have a tendency to get cold feet
* drinks and snacks for you and whoever's going to be with you
* a small facial sponge, for dabbing and sucking on
* body oil, fine talcum powder or lotion for back rubs
* music tapes/CDs and a battery-operated player
* a hairband and brush, soap, towel and flannel, toothbrush and paste, other toiletries as desired
* maternity pads (night-time sanitary pads will do) and knickers
Keep a water spray in the fridge until you leave for hospital. It's great for gentle cool-downs during labour.
You might also want to take a camera or camcorder. Check with the hospital first, as some units don't allow filming.
* a front-opening nightie (easier for breastfeeding)
* comfy clothes (such as a tracksuit and T-shirts)
* sandals or easy-fitting footwear
* knickers and maternity pads for heavy bleeding after birth
* nursing bras (at least two, as you can get sweaty in hospital and if your milk comes early your bra may get wet)
* towels (take one or two - your partner can bring in extras if you're required to stay longer)
* toiletries and cosmetics
* breast pads (to absorb leaks of colostrum and milk)
* phone card/coins (you can't use mobile phones in hospital)
* magazines and books
* writing materials
* personal music player/radio
* biscuits and snacks
* favourite breakfast cereal
* favourite tea bags
* fruit juice/mineral water
* babygrows and nappies for the baby
Remember, you'll need clothing for you and your baby to travel home in, although someone can bring that in once you've had your baby.
This is just a guideline though, as it depends what you feel you'll want/need during labour.
This is taken from http://www.bbc.co.uk/parenting/having_a_baby/pregnancy_hospital.shtml.