I am 27 weeks pregnant and until yesterday have no prior prenatal care by choice.?

The doctor I visited yesterday told me that by law he is obligated to report me to Social Services for investigation for lack of prenatal care. Is this legal? What do I do? At this point I trust this man as much as a used car salesman and don't wish to divulge anymore of my information with him. It is not my religion but as I told him I feel it is my right to choose for myself in matters of medical. Is this wrong?