Katharine Martha Houghton Hepburn (1878 – 1951) was an American feminist social reformer and a leader of the suffrage movement in the United States. Hepburn served as president of the Connecticut Woman's Suffrage Association before joining the National Woman's Party. Alongside Margaret Sanger, she co-founded the organization that would become Planned Parenthood. She was the mother of Katharine Hepburn.

Katharine Martha Houghton Hepburn (1878 – 1951) was an American feminist social reformer and a leader of the suffrage movement in the United States. Hepburn served as president of the Connecticut Woman's Suffrage Association before joining the National Woman's Party. Alongside Margaret Sanger, she co-founded the organization that would become Planned Parenthood. She was the mother of Katharine Hepburn.