Not all schools offer specialised tuition for learners who have a disability, although some do provide specially modified cars and instructors with sign language to help deaf students.
There are no reasons why a pregnant woman cannot learn to drive. Although the seat belt needs to be positioned so as to not cause discomfort, and turning in the seat for maneuvers can be awkward during the later stages.
The instructor can offer advice on this however. With the thought of taking a baby and pram etc on public transport, many pregnant women rush to take their test which can cause stress.
It is worth considering waiting until after the baby is born before taking lessons and the test so as to avoid any unnecessary stress.