Is it OK to swim while wearing contact lenses?

Only if you're wearing goggles with a firm seal. If you don't wear goggles, the contact lenses may float from your eyes and/or they will absorb the pool water, one consequence of which may be that they adhere quite firmly to the eye. If this occurs, it is advisable to leave the lenses alone for 10-15 minutes until the water in them has been replaced by natural tears before trying to remove them. Exposing your contacts to pool water also places you at risk of discomfort due to chlorine and infection from bacteria or other microorganisms.