Yes, done it twice. Both times I was around 20 weeks. To be honest I found the flight harder work than the parks as my feet swelled up like balloons and I had to keep drinking gallons of water! If I felt tired in the parks, we would just nip into an air con shop or restaurant for a breather. I never felt too bad. Plenty of fluids, a misting spray and a gentle itinerary worked for me!
If you are heavily pregnant when you travel, then dont be shy to rent a wheelchair, especially somewhere like Epcot. As long as you dont "abuse" the system (to queue jump, which, I am sure you would never do) then its fine.
Also, DH always mentioned it to the car park attendant who almost always let us park in VIP parking (except one old dragon at the MK who didnt seem to believe I was pregnant!). Sea World were exceptional on this score and as well as VIP parking, pointed out where the medical center was in case I needed anything. They really were great.
You will find a lot of the rides are billed as unsuitable for pregnant women. Of course, I wouldnt recommend going on Space Mountain, but I did do other "forbidden" rides, like Kilimanjaro Safari and Kali River rapids. Even if you decide not to ride, there is so much to see and do you wont feel left out.
Have a great tip.
Allie.
