"Typically, these girls have been abused at home and tend to have less self-worth because of their experiences.
They believe they're enjoying some form of elusive freedom, that they are in control of their own lives without parental authority.
"In the sex industry there are strong moral codes about what is right and wrong.
The sex workers we deal with are outraged when they see under-aged children on the streets." Inspector Ernie Riedeman of the Child Protection Unit said the unit did not have the capacity to do the kind of observation on the streets required to break child prostitute rackets.
David Fortune, project manager of Streets, an organisation working with street children, agreed that many girls living on the streets turn to prostitution as a way of making money quickly.
The organisation runs a drop-in centre where street children are offered services including counselling and it is in these sessions where Streets measures the scale of child prostitution.
The children are allegedly paid to sit up front and entertain drivers while they work and are then sexually exploited at the end of the day.
In recent research into child prostitution conducted at schools in the Western Cape, the issue of what is commonly referred to as "survival sex" was highlighted.
It was attended by 18 organisations which for the first time began sharing the information they have on child prostitution in South Africa.
Their initiative was sparked by an invitation to the South African government and non-governmental organisations to attend a world congress on commercial sexual exploitation of children in Sweden next month.
His information was underscored by Renee Rossouw of Ons Plek, a shelter for street girls.
But she said a survey conducted by the project had indicated that the percentage of street boys and girls involved in "survival sex" was equal.
But when they fall pregnant on the streets that myth is shattered," said Fortune.