I recently picked up a neoprene ball stretcher. I've been using it every other day for the last couple of weeks. I would like to make sure that its safe to use and wont cause any sterility. Does anyone have any insight on this? I know that some bikers face problems with sterility from riding their bikes with improper seats because its cuts off circulation to the testes. The stretcher doesn't entirely cut off circulation, however it slightly slows down circulation. Thanks