I'm self employed, so won't have any official maternity leave as such, but am planning to work part time as soon as I start feeling knackered, and keep working right up until my due date if I feel able to. Once the baby comes, I plan to have 2-3 weeks at home, then gradually return to work. My OH and I will be sharing the childcare equally as we run our business together, so I'm quite lucky in that respect. It also means that if I feel I need longer than a few weeks off, I can do.
In reality, I'll still be working right the way through though, as I'm sure I'll be doing paperwork from home with my newborn beside me, I just won't physically be 'at work'!