My water broke all over the people down the slimy end as DS was coming out. The were expecting it though, they have plastic gowns on. I was in full-on labour without my waters breaking.

So, water doesn't necessarily always break before. The OB said he had one the week before that did exactly the same thing. But, prolly best to call the hossy when it does, if your at home and don't have a purple face and sucking on the gas machine like a mad woman at the time (like me).