As a mother of 3, two of them I carried to term while still on the road, don't get me started how Fedex treats Pregnancies, as Operational Need pointed out, FAMILY FIRST. They will make you feel so bad, but as long as you have some day's or even if you need an LWOP day, TAKE IT...
Years ago, a manager had the nerve to tell me to have my 1st grader walk home by herself because he needed me to deliver. They put so much stress on mothers and fathers but especially mothers because we really worry. I know many cases of women couriers that did not carry to full term or simply lost their baby due to the heavy lifting. Good Luck to you and when you start to feel guilty or bad, just look in your child eye's.....