Edna Smith Primus had graduated from the University of South Carolina School of Law — the first black woman to do so, in 1972 — when barely one year later she was assigned a case that could have jeopardized her career.

She had been working at the time for the South Carolina Council on Human Rights as a volunteer lawyer when it dispatched her to Aiken, S.C., where an obstetrician had refused to deliver babies to women on welfare with two or more children unless they agreed to be sterilized.

The doctor’s refusal came amid a national public outcry over reports in The New York Times and elsewhere in the early 1970s that poor women, most of them black, were being involuntarily sterilized in the South.

Ms. Primus, who died on Nov. 29 at 75, was sent to Aiken to talk to mothers involved in the controversy there, some of whom had consented to sterilization. She told one woman who had undergone the procedure that the American Civil Liberties Union, for which Ms. Primus also volunteered at its South Carolina office, would represent the woman free of charge if she filed a lawsuit against the doctor.