Not the best option. Even if the window is itself waterproof, (vinyl or other) the flashing required to keep water out of the wall is just inviting future problems. I would suggest another location, or even a operable skylight. If you must place it in the shower, you may want to keep it shoulder height, (more for water then modesty.) You may also want to think of a smaller shower curtain to keep water away entirely at the window. Just options, they have been done for years that way, just not the best solution.

This can work best if it is placed in an area where it won't be in too much water. For example, placed high (above shoulder level) on the wall opposite the shower head.

HI -- I have a vinyl clad casement window with Low-E argon glass . No problems ,no issues .

Special safety glass is usually required if the window in a shower is below 60" above the finished floor.