Birth name

Scan of birth certificate of Marilyn Monroe
The birth certificate of Marilyn Monroe displays her birth name: Norma Jeane Mortenson.

A birth name is the name of a person given when they are born. The term may be applied to the surname, the given name, or the full name. Where births are officially registered, the full birth name entered onto a birth register or birth certificate may become the person's legal name by that fact alone.