"In the early 20th century, Margaret Sanger became one of the most avid proponents of contraception in the United States. By 1950, she and Katharine McCormick had contracted with biologist Gregory Pincus to develop an effective birth control pill. A collaborative effort by Pincus and other researchers led to trials of the pill in Puerto Rico, Haiti, and Mexico between 1956 and 1957, which pro-vided the basis for an application to the Food and Drug Administration for approval of the first oral contraceptive."