Some pieces of folklore are charming. Others are scary and pernicious. The one you quote is the latter. It is false. Period.
Dr. Rockoff
Dear Jackie,
When we got our hot tub we were told young girls should not go in it because it can destroy their eggs. As you probably know we are born with all our eggs. I thought you ought to know. I don't know any specifics,sorry.
Jackie:
Sometimes bacteria grow in hot tubs called Pseudomonas. This causes large, juicy pimples that come all ver the place. Treatment isn't needed, as the pimples go away all by themselves. Extra chlorine or other disinfecting methods helps prevent this. If there's doubt, have your kids see a doctor.
Best.
Dr. Rockoff