You can look at the park maps for the attractions with warnings - they are marked with a red triangle on the map and also on a sign at the entrance to the queue.
The wording for the general warning is:
WARNING! For safety, you should be in good health and free from high blood pressure, heart, back or neck problems, motion sickness, or other conditions that could be aggravated by this adventure. Expectant mothers should not ride.
For
Epcot here are the attractions with warnings:
- Mission Space the sign outside the attraction says that pregnant women are advised not the ride both the more tame (green side) and the more wild (orange side)
- Test Track
For
Magic Kingdom:
- Splash Mountain
- Big Thunder Mountain Railroad
- Tomorrowland Indy Speedway
- Space Mountain
For
Disney Studio
- Star Tours
- Rock N Roller Coaster
- Tower of Terror
For
Animal Kingdom:
- Kilimanjaro Safari
- Kali River Rapids
- Expedition Everest
- Primeval Whirl
- Dinosaur
Soarin' doesn't have any warnings that would affect pregnancy; just heights and possible motion sickness. There are some scents used on the ride (ocean air, oranges, pine) that you may want to be aware of if you are sensitive to smells.
The Safari and Kali River Rapids are listed because you can get unexpected hard bumps and drops during the course of the ride. Some moms late in pregnancy have posted it felt like the baby was using their bladder as a trampoline, so it was not exactly comfortable. Many people suggest that the Safari is less bumpy closer to the front, but it is still bumpy. We sit in the front seat because youngest DD needs to stay in her wheelchair; we still get bounced around a lot. It all depends on which ruts your ride car hits. I have also ridden it without DD, and have found the farther back seats are about the same (unless you are talking about the back 1/3 of the tram). Also, the tram is quite far off the ground; in case of a problem with the tram, you will need to get off of the tram without aid of the boarding area which raises you closer to the level of the seats.
The main drop is the reason for not riding Splash Mountain. The big drop takes you down at a very extreme angle at a high rate of speed (I think you get to 40 mph). At the bottom, your ride car stops abruptly. That sort of combination of fast speed drop at an extreme angle and then abrupt stop can theoretically cause placental abruption - where the placenta actually peels away from the wall of the uterus. That's the main reason for warnings at Splash Mountain.
For rides like Dinosaur, Star Tours, Test Track, Big Thunder Mountain you are not moving that fast, but experience sudden changes of direction that jerk you around a lot.
This is a link to the height calculator.
He will be too short for most of the ones with warnings.
There are lots of other things to do though.
For those he can ride, you will be able to wait with them until boarding and then leave without riding.
For those he is too short for, you and he will need to wait outside the attraction.
