Hi there, I have been looking into this as a main aspect of my experiment of rewiring my brain, and I found an article written by a doctor about the harmful effects of semen retention. I have no way of really knowing whether his sources are accurate because I don't know how to decipher the language in medical journals, but I thought this might be worth a look for you guys. http://www.actionlove.com/cases/case13176.htm I am hoping that if I decide to clean out my pipes, I will be able to do so without the need for porn. I am also hoping I can do it once a week without forming a habit of excessive masturbation. If you read my journal, you'll see I had a dream about my semen hardening.