Hi Kristy,
I am working up to 5 weeks before. Originally I was going to do an additional 2 more weeks but thought better of it just in case bubs comes early. Your body will tell you when enough is enough...obviously depending on the type of work you do. Check with your Human Resources department as they may need a certificate from your OB if you want to work after 6 weeks before your due date. Make sure your boss is looking after you!
Take care....Bianca