For bathrooms that get very humid, look for window coverings made of moisture resistant materials:
Palm Beach™ Polysatin™ Shutters are made with a UV-resistant polysatin compound that prevents them from warping, cracking, fading, chipping, peeling or discoloring over time, even in high-humidity. These shutters can cover any window shape, from arches and angles to hexagons.
EverWood® Alternative Wood Blinds have the look of genuine hardwood, but they’re actually guaranteed never to fade, yellow, warp or bow, even in areas with high heat or humidity.