The patient records are from a defunct clinic, Affordable Medical and Surgical Services in Kansas City, Kan. They show personal information such as names, birth dates, Social Security numbers and health history, including if the women had abortions.
The clinic was run by Krishna Rajanna, who lost his medical license in 2005.
Rajanna told the Kansas City Star he thought the records would be recycled before anyone saw them.
Local and state authorities are investigating.
Kansas law requires that all medical records be kept a minimum of 10 years. But hundreds of the discarded records were less than 10 years old.