I'd go - we had a labour bag in the car for five weeks, just in case! Didn't stop us going out - including for a walk that meant we were about an hour away from the car in the middle of a field at one point! I did have to call one thing off, but that was because of sciatica and I couldn't walk, let alone boogie all night.

If you go into labour in the middle of the musical or your waters break you may well get free tickets or a mention in the paper, so that could be fun!