Intersex people are as common in the world as ginger people, and green eyed people. Ginger people make up for two percent of the world's population, and so do intersex people. People with green eyes, such as myself, also make up that same percentage.
When people try to justify that there's only two genders and only two sexes by that oh the doctor just chooses what they think is the predominant sex. It is both ignorance to the scientific knowledge we have today and it is a direct violation to that person.