Hi,
Only been to one, my best mates, and I didn't want to get a pressi until the baby came as she didn't know what she was having. So I explained that I would be spoiling the baby after it came and I made a big pink and blue cake and made little icing baby toys for the top. Went down really well and I didn't turn up empty handed. We played some games and had some food and some virgin cocktails. I didn't have one myself though. Like redcrx says, I think its a bit of an American thing.