CHICAGO — In summer 1966, 17-year-old Leta Dally and her mother were driven by a stranger to an undisclosed location on Chicago’s South Side, where the recent high school graduate had an illegal abortion. She never knew the name of the doctor who terminated her 8-week pregnancy that night, or the exact address where the procedure took place. The driver parked the car and then walked with the teen and her mom through an alleyway to the backdoor of an indistinctive office building, which served as an underground abortion clinic operating in the years before the landmark case Roe v. Wade legalize…