This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
4 to 6 months
While piercings can be made anywhere on the scrotum, piercings made
through an outward facing fold of loose skin are more successful. The
piercing must not puncture the testicle sac itself which can lead to
very serious infection.
Scrotum piercings can be difficult to heal. The scrotum expands and
contracts which exerts stress on the entrances of the
piercing. Scrotum piercings are easily irritated by perspiration, lack
of air circulation, and friction against the wearer's clothing, thighs
and penis. Occasionally a ring or protrusion of soft, inflamed tissue
will form around the entrances of the piercing. Keep the piercing as
dry as possible and wear non-restrictive clothing that allows air
circulation. Usually the inflamed tissue recedes as the piercing
Initial jewelry: Captive bead rings in 14 to 10 gauge and 9/16" to
11/16" in diameter; the diameter of the ring should be at least 1/4"
wider than the width of the piercing. No more than 1/4 of the ring
should be through the piercing. A ring which is too small in diameter
will constrict the piercing and cause the piercing to migrate and
scar. Scrotum piercings can swell considerably during the first 4 to 6
weeks, and the ring must be wide enough to accommodate swelling.