On the topic of 'innies' versus 'outies'
When you are born the cord is cut immediately
after delivery and the result is a neat little knot.
As the wound heals, it takes on the vague shape
of the tissue caught between abdomen and knot.
The knot falls away and leaves the traditional
puckered appearance of the belly button. When the umbilical cord is cut after birth, it
is more likely to shrink down into an "innie" if
there is a good cut and only a small section of
cord. It will form an "outtie" if there is a longer
section of cord left.Whether
you end up an "innie" or "outie" depends on how
your body heals, and the skill of whoever tied the
knot.
Other than this, an "innie" can be turned into an
"outtie" by pregnancy or even a hernia, which is
why a larger percentage of mothers have
"outties" than the population as a whole.