I was 7 months preg with DD during a trip to "another" park. I used the restricted ride time for bathroom breaks and shopping - while DH and DS rode the rides. My OB gave me a copy of my file to carry with me - just in case. It certainly helped me feel better. Plus he said to CONSTANTLY drink water. He said that dehydration can bring on premature labor. So with all that water, I really needed them to ride a lot! LOL!
Make sure you enjoy all the shows. I know a friend that did WDW preg with twins. Her DH rented a wheelchair for her.