After my wife gets out of the shower , she itches all over, she thinks its the chlorine in the water, is it?

Probably: An easy fix to this is to go to the local health food store and buy a filtering shower head around $39 and the replacment cartridge is usually replaced every 4-6mths. This will eliminate the chlorine and most other chemicals. It has definitely helped me with this same problem.

Aquagenic Pruritus: Your wife's itch could be due to a condition known as aquagenic pruritus. Also there are some diseases in which bathing itch may be the presenting symptom (primary polycythemia or polycythemia vera). Aquagenic pruritus is not a discrete disease but a cluster of symptoms. I would see a board certified dermatologist for an evaluation and to help make the diagnosis.