Unless it's strung on PowerPro (which is like fishing line) then my understanding is the silk it's strung on will mildew and stink and you'll have to have it restrung. In other words, probably not.
Stci, No it's not advisable to shower with pearls on. Most experts say they should be the last thing you put on after getting ready for the day and the first thing off before retiring for the evening. If you are asking about showering, does that mean you are sleeping in them too?
The pearl board members ususally give advise they know is the least injurious to pearls. There are many sources of this information of which some are listed below. We never know if the person asking the question has pearls worth a few dollars or many thousands. So, I guess the question is not whether a person can shower in pearls, but is it prudent to do so and will it harm them or cause you to have to have them restrung frequently if you do choose to do so?
I would be worried about the silk stretching, harsh soaps, body lotion applied after the bath, shampoo, chlorinated water, spray deodorant and all the things in a bathroom that can harm pearls in the long run.
I think of pearls as being very delicate and also their stringing is, too. I'm very careful with my expensive set, but I wouldn't shower or sleep in any of them.
Since I read on PS that it's best not to sleep in any of your jewellery, I take it off at night. I used to sleep with my rings on. Now I want to preserve my things as much as possible, and also never shower in my jewellery. For years I showered and slept in my first pair of diamond studs, but my things are nicer now. I really can't imagine exposing my precious pearls to water, minerals, soap, night sweat if I'm hot in bed, the strand being jerked as I turn in my sleep, etc etc.