This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
Female nipple piercings should be made at the base of the nipple where
it meets areola. The piercing should not be made through the areola
unless the nipple is inverted.
Bleeding, if there is any, should stop within 12 hours. Wearing halved
panty-liners or nursing pads on the inside of the bra cups will keep
the piercing and the bra clean.
Bras exert pressure on the piercing, particularly if the bra is very
tight or if the wearer has large breasts. Too much pressure often
prolongs healing and can cause the piercing to migrate or scar. The
bra often pulls the ring downwards, creating leverage against the
piercing. Wearing the ring flipped up when wearing a bra often reduces
pressure. Bras with seams across the nipple easily irritate the
piercing. Most women find wearing an athletic bra more
comfortable. Wearing open nursing bras or cutting out the center of
the bra cups will eliminate pressure on the piercing while providing
support.
Many women with large breasts have found barbells to be much more
comfortable than rings during healing. Many women who have experienced
prolonged or difficult healing while wearing rings have successfully
healed their piercings after switching to barbells. The barbell balls
should be small enough in diameter so that they do not create pressure
against the areola which can cause the piercing to migrate.
Piercings made through flat or inverted nipples are more likely to
migrate or reject if the nipple continues to flatten or invert with
the jewelry in place. In some cases the piercing will shift or migrate
slightly while healing but will eventually settle. If the nipple is
more easily pinched vertically, a vertical piercing is more likely to
be successful. In some cases, the nipple is more easily pinched at a
diagonal, or perpendicular to the long axis of the nipple. The
piercing should not be made excessively deep on the assumption that it
will migrate into place. 12 and 10 gauge piercings usually resist
migration. Piercings in inverted nipples are sometimes more successful
when curved barbells are worn. A curved barbell will eliminate
pressure between the barbell balls and the areola.
The menstrual cycle may cause piercings to become irritated or more
sensitive. The swelling and water retention usually associated with
menses may cause the nerves in the nipple to become pinched against
the jewelry.
It is not uncommon for the discharge released during healing to seep
from the front of the nipple via the penetrated milk ducts.
Initial jewelry: Captive bead rings in 14 to 10 gauge and 5/8" to 1"
in diameter; the diameter of the ring should be at least 1/4" wider
than the width of the piercing.
 
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