I read heaps of posts about people saying their labour was X hrs and X mins and I wonder how they time it. People ask me "how long were your labours?" and I'm not really sure how to answer. Do you time it from first symptom/pain or what? Is there a "rule' that people follow for this?

With my first, it started with water breaking but no contractions until few hours later. So how many hours do I say - baby was born 10hrs after water breaks, 7hrs after 1st contraction, and 3hrs after 'strong' contractions (from 4cm dilated). So how long was my labour? With my second I had mild pain all night but didn't actually know I was in labour until 2 hours before baby was born (arrived at hossy 10cm dilated, baby born 1hr later) - so how long do I say my labour was here? Everyone else seems to know theirs!