Hi.
I hve seen pictures with (injection) needles put on or trough the testicles as kind of temporar play piercing. I would like to try it on myself. But on the other had I also want to keep my fertility.
Do any of you have experiences on how to do this safely, what needle sizes to use and how often this can be done without mentionable loss of fertility?

Thanks for the answer. Yes, I want to get the needle into the nut itself. There is a study on fine needle aspiration cytology for fertility analysis in dogs, and it states that using needles size 21G does not seem to have any measureable effect, as long as it is done on an analytic level (amount)

I am not a dog, and there may be some biological differences. As I am somewhat bigger than most dogs these differences may even count in my favor.
I hope some members here might have some own experiences to add.