The combined oral contraceptive pill's development traces to a specific, somewhat improbable collaboration formed in the early 1950s. Margaret Sanger, the birth control movement's most prominent American activist, and Katharine McCormick, an heiress and one of the first women to graduate from MIT, who provided the bulk of the project's private funding — reportedly around $2 million of her own money, since federal and most private research funding for contraceptive research was essentially unavailable given the era's restrictive social and legal climate around birth control — recruited biologist Gregory Pincus to lead the scientific research. Pincus partnered with John Rock, a Catholic obstetrician and fertility researcher at Harvard, whose religious standing and clinical credibility helped provide crucial legitimacy and access to clinical trial subjects that the more controversial Pincus and Sanger might have struggled to secure alone.
The resulting drug, based on synthetic progesterone research building on earlier work by chemists including Russell Marker and Carl Djerassi, underwent clinical trials in Puerto Rico beginning in 1956 — chosen partly because Massachusetts law at the time still restricted contraceptive distribution and research — before receiving FDA approval for contraceptive use in 1960, under the brand name Enovid. Within just a few years, the pill became one of the most widely adopted medications in American history, with by some estimates over six million American women using it by the mid-1960s, fundamentally changing how women could plan families, pursue education, and participate in the paid workforce.