This article is from the Piercing FAQ, by Anne Greenblatt with numerous contributions by others.
4 to 8 months
The shape of the navel varies from person to person. Not all navels
can be successfully pierced. An "innie" navel with a prominent lip or
rim is most likely to be successfully pierced. Navels lacking a
distinct lip often cannot support a piercing and the piercing migrates
or rejects. The upper lip is usually more prominent than the lower
lip. Often, there is a natural indentation or slight wrinkle about the
navel at the appropriate location of the top entrance of the
piercing. The entrances of the piercing should be placed equidistant
from the edge of the lip to make the piercing as close to
perpendicular to the tissue as possible.
The shape of one's navel, not one's overall bodyweight, determines
whether or not a navel piercing is likely to be successful. Some
larger women do posess well-suited navels with a distinct lip.
Placement of the piercing should be determined after examining the
navel when the piercee is in different body positions. The dimensions
of the jewelry should be chosen after measuring the width of the
piercing. The navel lip will often stretch and flatten when the
piercee reclines.
Navel piercings are usually placed vertically and centrally. However,
an asymmetrical navel should be pierced according to its shape. If the
top lip is more prominent and the inside of the lip forms a wrinkle,
the piercing must be placed within the wrinkle. If the bottom of the
navel forms a wrinkle, the piercing should be centered above the
wrinkle as the jewelry will tend to lay in the wrinkle. In some cases
the most prominent lip is situated diagonally, requiring a diagonal or
angled piercing. Please see section 2D.1b "Angled Navel Piercings."
A curved barbell is more appropriate than a ring if the piercee's
waist folds at the navel when he/she is sitting - a ring would be
pushed to one side, causing the piercing to be uncomfortable, heal
crookedly, and scar. If the waist folds so much that the navel
disappears when the piercee is seated, the piercing will be
uncomfortable and unlikely to heal well, and it may reject
completely. In this case, piercing should be discouraged.
A curved barbell is more appropriate than a ring if the lip is not
distinct or if it inverts when the piercee reclines. If the lip is not
distinct, the width of the piercing often exceeds 1/2", requiring a
ring of an uncomfortably large diameter.
Wearing waistbands over the piercing must be avoided while the
piercing is healing, regardless of the style of jewelry worn. Wearing
waistbands over the piercing will prolong healing and can cause the
piercing to scar, migrate, or reject completely. If a ring is worn,
the waistband will push it to one side, causing the piercing to be
uncomfortable, heal crookedly, and scar. After the piercing has
healed, it can be irritated if tight waistbands are worn over the
piercing.
Initial jewelry: Curved barbells in 14 to 10 gauge and 3/8" to 1/2" in
length; the barbell should be 1/8" wider than the width of the
piercing when the piercee reclines. A barbell which is too short will
constrict the piercing and restrict blood circulation. Captive bead
rings in 14 to 10 gauge and 3/8² to 1/2" in diameter. No more than 1/3
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 scar
or migrate. Teardrop and oval-shaped rings designed specifically for
navel piercings may be worn when a less obtrusive ring is desired, but
they do not provide the same benefits as curved barbells.
"Outie" Navels
An "outie" navel is a herniated umbilicus, or remnant of the umbilical
cord, which did not heal correctly and retract inwards after
birth. Some "innie" navels contain a herniated umbilicus which can
easily be felt under the skin and usually causes the navel to be
extremely asymmetrical. The dormant blood vessels of the umbilicus
remain connected to the interior of the abdomen. An untreated
infection could potentially travel via the umbilicus to the liver.
Navel Piercings and Scars from Laparoscopic Surgery
In some cases the scar does not heal correctly and is a potential
passageway for bacteria or untreated infection to travel into the
abdominal cavity. Piercings should not be made through or around the
scar.
Navel Piercings and Pregnancy
During pregnancy the length of the piercing will stretch and flatten;
the gauge will not stretch. Some women with healed piercings have
successfully worn jewelry throughout their pregnancies. In other cases
the ridge of the navel expands and flattens so much as to make the
jewelry uncomfortable. Monofilament nylon or teflon can be more
comfortable than metal jewelry because it is softer and more flexible.
After delivery the navel will return to its original shape but the
skin will very loose and the piercing may sag.
If the piercing is still healing it is unlikely that the piercing can
be maintained; as the stomach enlarges the pressure could easily cause
the piercing to reject. Infection must be avoided; a serious infection
could travel to the interior of the abdomen and possibly affect the
pregnancy or the baby. In the interest of maintaining good health and
reducing risks that could affect your pregnancy, abandoning the
piercing may be the best option.
Women who have had children usually do not have a risk of the piercing
migrating or rejecting because the skin has been stretched.
 
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