The pill: a history
1916: Margaret Sanger, founder of Planned Parenthood Federation of America, opens first birth control clinic in the United States.
1941: Penn State organic chemist Russell Marker discovers how to make synthetic progestin from a Mexican yam, the basis for hormonal birth control.
1950s: Sanger and philanthropist Katharine Dexter McCormick, both in their 70s, underwrite research for a "magic pill.'' They turn to scientist Gregory Pincus, who teams with pioneering Harvard ob/gyn Dr. John Rock.
1956: Clinical trials of the pill begin in Puerto Rico, to get around anti birth control laws in many states.
1957: FDA approves use of the pill to regulate menstrual periods, although many women take it for birth control.
May 9, 1960: Advisory committee of the FDA approves the drug — called Enovid — for contraception. Full approval by the FDA follows on June 23.
1965: Pill is legal in all states when U.S. Supreme Court decides in Griswold vs. Connecticut that married couples may use birth control without government interference.
1970: U.S. Sen. Gaylord Nelson, D-Wis., holds hearings into the pill's safety and whether women understand the risks, contributing to FDA requiring an information insert in packages.
1970: President Richard M. Nixon signs Title X of the Public Health Services Act, providing federal funding for family planning services including the pill.
1972: U.S. Supreme Court decision in Eisenstadt vs. Baird legalizes contraception for unmarried people.
1988: At the FDA's urging, drug companies remove the original high-dose oral contraceptives from the market, which had gradually been supplanted by safer, lower-dose formulations.
1990: According to the annual FDA Consumer report, the pill is considered safe and effective by the government, the medical establishment and consumers.
Today: Nearly 19 percent of all women between 15 and 44 use the pill, or nearly 30 percent of all women who use birth control.
Sources: Planned Parenthood, PBS.org