As long as you are able to avoid the potentially communicable diseases associated with possible ill effects/birth defects/endangerment to your or the fetus' health condition, I'd say work where and when and for however long you feel like working before delivering. There's nothing wrong, either, with being at home w/baby for at least the first few months/years while they develop their immunities before being shoved into the germ world of daycare outside of home. Just remember one very important lesson I learned while having babies and going to nursing school then hurrying up to enter the nursing profession: babies grow up MUCH too quickly and it's time you cannot possibly get back....those milestones, smiles, cooes, first steps, crawling, transitioning from infant to toddler, etc. are MUCH too precious to miss much of while trying to be superwoman in today's unfair working world.
You must do what is right for you and baby and bonding together as a family unit with hubby. Do what you feel in your heart and soul what is right and trust me, you'll know yourself inside when it's time to decide for sure.
I wish you luck....remember, baby and you and hubby first....careers can be started, resumed, maintained at a later date and you have decades to work.
Oh, and CONGRATUALTIONS! ON YOUR PREGNANCY...TAKE CARE OF YOU, YOUR HEALTH AND WELLBEING ARE FIRST AND FOREMOST DURING THIS AWESOME TIME OF GROWING THAT MIRACLE INSIDE! Let us know what you decide and how you're doing!