My labour with my first actually began around 8:30am! But it went for 19 hours so it took me well into the following night - that was mainly due to an epidural that slowed down what had been quite a progressive labour. I was glad that most of my labour (I did the first 11 or so hours at home with no pain relief) took place during the day because there was something about being in labour during the day that helped me to focus and not freak out.