12 February 2009
Birth control pill
The invention: An orally administered drug that inhibits ovulation in women, thereby greatly reducing the chance of pregnancy. The people behind the invention: Gregory Pincus (1903-1967), an American biologist Min-Chueh Chang (1908-1991), a Chinese-born reproductive biologist John Rock (1890-1984), an American gynecologist Celso-Ramon Garcia (1921- ), a physician Edris Rice-Wray (1904- ), a physician Katherine Dexter McCormick (1875-1967), an American millionaire Margaret Sanger (1879-1966), an American activist An Ardent Crusader Margaret Sanger was an ardent crusader for birth control and family planning. Having decided that a foolproof contraceptive was necessary, Sanger met with her friend, the wealthy socialite Katherine Dexter McCormick. A1904 graduate in biology from the Massachusetts Institute of Technology, McCormick had the knowledge and the vision to invest in biological research. Sanger arranged a meeting between McCormick and Gregory Pincus, head of the Worcester Institutes of Experimental Biology. After listening to Sanger’s pleas for an effective contraceptive and McCormick’s offer of financial backing, Pincus agreed to focus his energies on finding a pill that would prevent pregnancy. Pincus organized a team to conduct research on both laboratory animals and humans. The laboratory studies were conducted under the direction of Min-Chueh Chang, a Chinese-born scientist who had been studying sperm biology, artificial insemination, and in vitro fertilization. The goal of his research was to see whether pregnancy might be prevented by manipulation of the hormones usually found in a woman.It was already known that there was one time when a woman could not become pregnant—when she was already pregnant. In 1921, Ludwig Haberlandt, an Austrian physiologist, had transplanted the ovaries from a pregnant rabbit into a nonpregnant one. The latter failed to produce ripe eggs, showing that some substance from the ovaries of a pregnant female prevents ovulation. This substance was later identified as the hormone progesterone by George W. Corner, Jr., and Willard M. Allen in 1928. If progesterone could inhibit ovulation during pregnancy, maybe progesterone treatment could prevent ovulation in nonpregnant females as well. In 1937, this was shown to be the case by scientists from the University of Pennsylvania, who prevented ovulation in rabbits with injections of progesterone. It was not until 1951, however, when Carl Djerassi and other chemists devised inexpensive ways of producing progesterone in the laboratory, that serious consideration was given to the medical use of progesterone. The synthetic version of progesterone was called “progestin.” Testing the Pill In the laboratory, Chang tried more than two hundred different progesterone and progestin compounds, searching for one that would inhibit ovulation in rabbits and rats. Finally, two compounds were chosen: progestins derived from the root of a wild Mexican yam. Pincus arranged for clinical tests to be carried out by Celso- Ramon Garcia, a physician, and John Rock, a gynecologist. Rock had already been conducting experiments with progesterone as a treatment for infertility. The treatment was effective in some women but required that large doses of expensive progesterone be injected daily. Rock was hopeful that the synthetic progestin that Chang had found effective in animals would be helpful in infertile women as well. With Garcia and Pincus, Rock treated another group of fifty infertile women with the synthetic progestin. After treatment ended, seven of these previously infertile women became pregnant within half a year. Garcia, Pincus, and Rock also took several physiological measurements of the women while they were taking the progestin and were able to conclude that ovulation did not occur while the women were taking the progestin pill.Having shown that the hormone could effectively prevent ovulation in both animals and humans, the investigators turned their attention back to birth control. They were faced with several problems: whether side effects might occur in women using progestins for a long time, and whether women would remember to take the pill day after day, for months or even years. To solve these problems, the birth control pill was tested on a large scale. Because of legal problems in the United States, Pincus decided to conduct the test in Puerto Rico. The test started in April of 1956. Edris Rice-Wray, a physician, was responsible for the day-to-day management of the project. As director of the Puerto Rico Family Planning Association, she had seen firsthand the need for a cheap, reliable contraceptive. The women she recruited for the study were married women from a low-income population living in a housing development in Río Piedras, a suburb of San Juan. Word spread quickly, and soon women were volunteering to take the pill that would prevent pregnancy. In the first study, 221 women took a pill containing 10 milligrams of progestin and 0.15 milligrams of estrogen. (The estrogen was added to help control breakthrough bleeding.) Results of the test were reported in 1957. Overall, the pill proved highly effective in preventing conception. None of the women who took the pill according to directions became pregnant, and most women who wanted to get pregnant after stopping the pill had no difficulty. Nevertheless, 17 percent of the women had some unpleasant reactions, such as nausea or dizziness. The scientists believed that these mild side effects, as well as one death from congestive heart failure, were unrelated to the use of the pill. Even before the final results were announced, additional field tests were begun. In 1960, the U.S. Food and Drug Administration (FDA) approved the use of the pill developed by Pincus and his collaborators as an oral contraceptive.Consequences Within two years of approval by the FDA, more than a million women in the United States were using the birth control pill. New contraceptives were developed in the 1960’s and 1970’s, but the birth control pill remains the most widely used method of preventing pregnancy. More than 60 million women use the pill worldwide. The greatest impact of the pill has been in the social and political world. Before Sanger began the push for the pill, birth control was regarded often as socially immoral and often illegal as well. Women in those post-World War II years were expected to have a lifelong career as a mother to their many children. With the advent of the pill, a radical change occurred in society’s attitude toward women’s work.Women had increased freedom to work and enter careers previously closed to them because of fears that they might get pregnant. Women could control more precisely when they would get pregnant and how many children they would have. The women’s movement of the 1960’s—with its change to more liberal social and sexual values—gained much of its strength from the success of the birth control pill.