There was a theory investigated by the Channel Four
television series, Secret Lives
that Marie Stopes a had a hidden agenda in encouraging birth control
rights for women.
The theory goes that Stopes felt that the rich in the world were supporting the poor. In her own educated way she felt that the poor were doing nothing to help themselves and therefore they were a burden upon society, breeding exessively and expecting others (the rich) to support them. Much like the Darwinist theory of survival of the fittest. Hence her belief that if women had more access to birth control the number of children per household would drop and subsequently poverty would be more controlable. Of course publicly, Stopes encouraged birth control as a way in which women could control their own bodies and not as a means of social control.
The programme also investigated Stopes own private life, discussing that her own son was brought up entirely at home without any contact with outside influences, especially children. He was treated as a social experiment as Stopes believed she could 'create' the perfect citizen.