You only get so many days for short term disability and if you go over those days (and maternity leave
may count in your short term disability
benefits like it did mine)-- you get different pay. I ended up working until a week before my due date because I wanted time after the baby-- as much as possible. Does that make sense?
Honestly, the best thing to do is check with your own company and their benefits. Do you have an online site that you can look at for your employer?