Changes

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====Masturbation for intact teens====

<blockquote>

I am happy that you and your son can talk candidly about sex. You can explain to him that, just as you cautioned him not to forcibly retract his [[foreskin]], he needs to be careful with his foreskin when he masturbates. Here’s why: One or two millimeters under the penile skin is a smooth muscle sheath called the [[dartos]] fascia. The dartos fascia covers the shaft of the [[penis]] and extends to the tip. The dartos fascia muscle fibers near the tip of the foreskin form a sphincter-like structure—or a ring—that acts like a one-way valve and shields the urinary opening.