Her "bits" were female. According to wiki...
//Campbell was born with a genital malformation and, following the medical advice of that time, was raised as a boy despite being female. She moved to New York City to attend the Fashion Institute of Technology and began working as a model. In 1970 she had corrective surgery for her congenital vaginal malformation, funded by her grandmother. She legally changed her name from George William Ziadie to Georgia Arianna //
Yikes...she went to Fashion Institute of Technology about the same time I did. Small world.