Sålunda talar den allvetande Skräphögen (Ja, Wikipedia, alltså...) i saken.
http://en.wikipedia.org/wiki/Adam%27s_apple
"The larynx grows in males and females during puberty. However, the Adam's apple is generally more prominent in adult men than in women or pre-pubescent girls or boys. (The growth of the larynx is the reason for voice cracking in boys and girls during puberty.)
For some transwomen, the Adam's apple remains more prominent than desired, sometimes remedied by a trachea shave, a type of plastic surgery to reduce the size of the Adam's apple.
Despite this, it is not extremely uncommon for biological females to have a small to large Adam's apple."
Case closed, eller? Det lämnas ju trots allt en liten öppning. "For some transwomen..."