Question: Why do some people have innies belly buttons while others have outies???

Kirsty Ross answered on 20 Jun 2012:

Only 10% of the population have outie belly buttons! It used to be thought that it had something to do with where the umbilical cord was clamped after birth. However there is no evidence for that. It is essentially a random process of scar formation. Mums who are innies and become pregnant often find it pops out during later stages in labour!