I'm starting to wind down now (31 wks) due to spd but will be on mat leave from 36 weeks. With dc1 I took my holiday from 32-36 weeks then mat leave started. I was still being sick at 34 weeks and had a history of miscarriage so was advised to not get too tired.
I worked until 39 weeks with dd, she arrived 41+5. I want to make the most out of mat leave. I think with dc2 it depends whether you will be more rested at work or at home. For me sitting on an adjustable chair in the office sounds more comfy than running around after another kid!