Birth, Under Control

Birth, Under Control

By Andrea Natalia Rivera Rosario

Volume 23, number 1, Science Under Occupation

Versión en español

Artwork by Sophie Standing

 “Porto Ricans are beyond doubt the dirtiest, laziest, most degenerate and thievish race of men ever inhabiting this sphere. What the island needs is not public health work but a tidal wave or something to totally exterminate the population. I have done my best to further the process of extermination by killing off eight and transplanting cancer into several more.”

– Dr. Cornelius Rhoads, MD, who was sent to Puerto Rico by the Rockefeller Institute to conduct a public health study in 1931

Modern medicine has displaced religion as the prime author of miracles. Yet we rarely ever stop to think about the process that led to the development of new medicines, let alone the social situations that surround them. Learning about the countless ethics violations that have paved the way for modern science is a hard pill to swallow. But these discoveries become no less useful or important to society if deemed unethical. Instead, by being critical of the practice of science itself we can move past the idea that it is somehow sacrosanct. In this way, we honor the lives of those sacrificed in the pursuit of knowledge.

Racism, sexism, and prejudice fueled various (un)scientific experiments in the United States and its territories, including Puerto Rico. In the mid-twentieth century, the pharmaceutical company G.D. Searle carried out a number of trials on the Caribbean island to assess the potential side effects of a new form of hormonal birth control: The Pill.1 These trials, motivated by American colonial and imperialist ideology, not only put unconsenting women’s lives at risk but also showed the measures the US was willing to take to reduce overpopulation on the island.

The Fate of The Colony

It’s nearly impossible to describe the motivation behind the use—and abuse—of science in Puerto Rico without addressing the archipelago’s complicated colonial history with the United States. During the Spanish-American War, General Nelson A. Miles’s troops invaded the southwestern town of Guánica on July 25, 1898. Following the war, the Spanish crown sold the Philippines, Puerto Rico, and Guam to the US for a measly $20 million.2 Due to its privileged geography in the Caribbean, the Puerto Rican archipelago (composed of the main island, Vieques, Culebra, and a handful of unpopulated cays) served as an optimal entry and exit port to the Americas. As a consequence of its strategic military and commercial value, Puerto Rico remains to this day a US colony, doomed to a perpetual state of “in betweenness.”

Puerto Ricans were ruled by an American-appointed civil government until 1952, which marked the introduction of the Puerto Rican Constitution. Officialized on the fifty-fourth anniversary of the invasion, this document formally transformed the colony into El Estado Libre Asociado de Puerto Rico (The Free Associated State of Puerto Rico). Misleading as it was, Puerto Rico did not instantly become free, associated, nor a state. Instead, this constitution papered over the existing colonial status.

Along with the introduction of the new constitution in the 1950s came a targeted plan to prioritize the economic development of Puerto Rico. Luis Muñoz Marín—in office from 1949 to 1965—was the archipelago’s first elected governor and oversaw its journey into democratic development. Fueled by a New Deal-esque ideology, his administration instituted Operation Bootstrap (Operación Manos a la Obra) in 1947 to modernize Puerto Rico through industry, and to reduce key markers of poverty.3 All areas of Puerto Rican life had to see drastic changes in the name of progress: work, home, values, infrastructure, and, most importantly, the family unit. What had been a gradual transformation from a primarily agrarian economic system to one based on manufacture and industry suddenly picked up speed during the mid-1900s. According to US Census data from 1940, about 566,000 Puerto Ricans lived in urban areas, where most factories were located. By 1950, this number was nearing 900,000.4

Despite apparent economic prosperity, Operation Bootstrap left a higher rate of unemployment and a lower rate of workforce participation. Industrialization was simply not enough to cover the gaps left by the lack of agricultural jobs.5 Operation Bootstrap did, however, succeed in instilling in the public a capitalist state of mind. There was a drive for more of the good (economic growth, urbanization, jobs) and less of the bad: poverty. Over time, many institutions and experts dedicated their work to finding the root of poverty on the island. Eventually, social scientists settled on a culprit: the Puerto Rican population was growing too much, too fast.6

The colonial government—as well as its US homolog—directed political measures against the overpopulation problem. Since the 1920s, well before the industrial boom, authorities had been paying close attention to the “excessive” number of Puerto Ricans. One of the metrics used to assess the situation was the supposed high fertility rate of Puerto Ricans.7 Population demographers and sociologists established a causal relationship between alleged sexual promiscuity and increased fertility. This led to population control efforts that primarily targeted the reproductive behavior of Puerto Ricans—especially women.

Restricted Reproduction: The Puerto Rican Experiment

And so a number of birth control programs were put into action. Clinics were opened throughout the archipelago in the early 1930s to reduce poverty by limiting the reproduction of lower and working classes.8 However, it was the elite and upper class women who were more receptive to these family planning policies, which prompted concerns that the island was undergoing race suicide—a concept rooted in eugenics which describes the extinction of “desirable” populations and the simultaneous increase of the “unfit.”9

The 1930s also marked the arrival of Dr. Clarence Gamble, a physician and heir to the Procter & Gamble fortune. Gamble, an aggressive eugenicist, saw Puerto Ricans as a threat to Americans. These people were good for the fields and factories, but nobody wanted them invading the mainland.10 What would the country do with all those poor, ambiguously pigmented, Spanish-speaking “Americans?”

Gamble was already recognized for birth control programs and experiments, so when contraception (including surgical sterilization) became legal in Puerto Rico in 1937, he saw an opportunity to continue exploring his methods.11 Under his supervision, various reproductive health clinics were established on the island in the latter part of the decade.

While promoting sterilization as a quick and easy way to achieve lower population densities, Dr. Gamble took creative liberties by prescribing reversible contraception products of unproven efficacy. He promoted spermicidal jellies and creams under the guise that these were foolproof and suitable for Puerto Rican women.12 Mostly a mix of acids, solvents, and detergents, Gamble was well aware that these topical solutions were rarely effective.13

Puerto Rico, with its vast population of poor and illiterate women, provided Gamble and American drug companies with an ideal environment for mass clinical testing of contraceptives. His presence—along with his reputation and professional connections—was instrumental in sealing the archipelago’s fate as a social laboratory. Before, small-scale family planning initiatives were usually led by feminist nurses and social workers. Dr. Gamble’s model of research, which put the power of population control into the hands of American physicians, would send research efforts down a darker, more questionable path.14

The Magic Pill

Dr. Gregory Pincus, a former assistant professor at Harvard University and human sexuality researcher, is credited as the mastermind of the Puerto Rico birth control trials. Pincus, together with Dr. John Rock, a gynecologist at Harvard, felt a moral obligation to combat overpopulation, particularly among “primitive people” who, they believed, had a higher birth rate.15 Pincus and Rock carried out a series of experiments on women to prove the safety of an oral contraceptive they called Enovid.

Enovid merged both doctors’ previous research. In Pincus’ lab, injections of progesterone and estrogen—hormones known to control the female reproductive cycle—into female rabbits yielded promising contraceptive results. Simultaneously, Rock used the same two hormones in his clinic to induce pregnancy in patients presumed to be infertile. In 1953, they embarked on a journey to find how these chemicals could suppress fertility.16

Around the same time, Margaret Sanger, a nurse and co-founder of Planned Parenthood, was advocating for birth control accessibility. Sanger was passionate about women’s rights to voluntary maternity. She was also aware of the role family planning had in reducing the number of women who lived below the poverty line. It was this pursuit that led her to establish contact with noted eugenicists—especially Dr. Clarence Gamble, who became a close acquaintance. Sanger had also become interested in Dr. Pincus and Dr. Rock’s research as a way to achieve her ultimate goal: a safe and effective birth control pill. By the mid-1950s, she had convinced her fellow feminist—and heiress of a $35 million fortune—Katharine McCormick to fund the pair’s scientific experiments.17 They had a patron and a pill; all they needed was a sponsor. After two pharmaceutical companies refused to participate in human trials, deeming the potential experiments dangerous and unethical, a third—G.D. Searle—took on the challenge.18

Uninformed Consent

It’s worth mentioning that regulations on human research were not as strict in the 1950s as they are today. The bills that established modern ethical principles—such as the Belmont Report of 1979, which established the notion of informed consent—would be written after the experiments were over and Enovid was already on the market. In Puerto Rico, already a “social laboratory,” the lack of research regulations was twofold. Laws were more lax and birth control efforts were already commonplace, so the new pill flew under the radar as just another means to reduce overpopulation.19

In 1954, small trials were conducted with patients living in the psychiatric facility of Worcester State Hospital in Massachusetts. The researchers ended up deeming this experiment inconclusive because of the assumption that the patients were not sexually active.20 Pincus and Rock then turned to Puerto Rico in search of a larger, tractable test group. An initial study started in 1955 and enrolled twenty female medical students from the University of Puerto Rico. In Reproducing Empire, Laura Briggs writes that, although these young women were able to consent, their grades were reportedly contingent on their participation in the trial. Despite being coerced into volunteering, they could not keep up with the daily pill-taking and testing required: vaginal smears, temperature measuring, monthly urine collections, endometrial biopsies, and even occasionally laparoscopies. The trial was dropped.21

By 1956, Pincus had moved into even larger Puerto Rican populations: residents of a housing project in Río Piedras, in the capital of San Juan, and patients of Ryder Hospital, in the eastern rural town of Humacao. The six hundred women enrolled in the trial had usually been turned down for sterilizationbecause they had fewer than three children.22 Half of these women ended up abandoning the tests, and the trials produced practically unusable results. Enovid had not, in fact, lowered the birth rate among the women. Twenty out of 295 Río Piedras participants became pregnant in the first eighteen months and the researchers observed a 79 percent rate of pregnancies in the four months following the trials.23

In addition, side effects (nausea, vomiting, vaginal bleeding, and severe headaches) made a large number of subjects miserable, often warranting trips to the hospital. Two female physicians who supervised his trials on the archipelago, Dr. Edris Rice-Wray and Dr. Adeleine Satterthwaite, raised alarms on the inhumane practices that led these misinformed women to suffer distressing side effects—reporting that many presented damage to uterine structures;some were even diagnosed with reproductive cancers, and three women died.24 Pincus wrote off these effects as resulting from misuse of the hormones and lack of dosage consistency and persevered, underreporting his setbacks and conducting further experiments in Haiti and Mexico. Enovid was finally approved by the FDA in 1960.25

Debates about the participants’ (un)informed consent have continued in the decades following Pincus and Rock’s studies. In her 1982 documentary about sterilization and population control practices in Puerto Rico (La Operación, The Operation), Ana María García shares the testimony of two participants. The women reported no knowledge of the composition or dosage of the pill, and one recounted the nausea, dizziness, and fainting she experienced following the treatment.26 Almost thirty years later, they did not know they were the first women in the world to use Enovid and had no idea that the formulation they were initially given had much higher doses of progestin than are necessary to prevent pregnancy.27 None of these women were compensated for their months of commitment to the trials.

For The Women

There is no denying that the pill ushered in a revolution. For feminists, and for women in general, a convenient method of contraception meant having a new way to reclaim autonomy over their bodies. In the decades following the trials, many of us have reaped the immense benefits of the researchers’ work—as well as the countless hardships endured by their test subjects.

We must recognize the unequal situations that made this scientific advancement possible. At $11 a month, Enovid was too costly for the working women of Puerto Rico.28 Initially the subjects of population control measures—the very efforts that brought Pincus to the island in the first place—lower and middle class women saw no change in the contraception methods available to them. Most still turned to sterilization, the most invasive of their options, as a means of family planning. By the 1970s, 35 percent of all Puerto Rican women were sterilized.29

Poverty was not alleviated by birth control legislation, and overpopulation continued to serve as a pretext to exploit Puerto Ricans through unregulated experimental treatments. Today, poverty and lack of resources are still used to justify oppressive colonial policies in Puerto Rico. The Fiscal Oversight and Management Board, put in place by Congress’ PROMESA Act in 2016, is in charge of alleviating the debt-ridden archipelago’s economy.30 This body controls the financial and economic future of Puerto Rico and is composed of seven members unilaterally chosen by the President of the United States—for whom Puerto Ricans have never been able to vote in a general election. Like the birth control programs, the Board’s orders come at the recommendation of social scientists and foreign experts. Puerto Ricans, yet again, have no say in the matter.

About the Author

Andrea Natalia Rivera Rosario is an undergraduate student at the University of Puerto Rico, Río Piedras. She is currently a Cell and Molecular Biology major with a minor in Women & Gender Studies, as well as Medical Humanities. She is passionate about scientific research, women’s rights in Puerto Rico, and community education.


  1. Drew C. Pendergrass and Michelle Y. Raji, “The Bitter Pill: Harvard and the Dark History of Birth Control,” The Harvard Crimson, September 28, 2017,
  2. Editors, “Treaty of Paris Ends Spanish-American War,”, December 10, 2019,
  3. María Elena Carrión, “Operación Manos a La Obra,” Encyclopedia de Puerto Rico, September 15, 2014,
  4. US Department of Commerce, “Puerto Rico: 2010,” United States Census 2010,
  5. Carrión, “Operación Manos a la Obra.”
  6. Schroeder, Theodore, “Porto Rico’s Population Problem,” Birth Control Review 16, no. 3 (1932): 71–72.
  7. Laura Briggs, Reproducing Empire: Race, Sex, Science, and U.S. Imperialism in Puerto Rico (University of California Press, 2002), 83-84.
  8. Briggs, *Reproducing Empire, 93-97.
  9. Briggs, “Demon Mothers in the Social Laboratory,” 115-116; Sanger, Margaret, “Birth Control and Racial Betterment,” Birth Control Review (February, 1919).
  10. Briggs, Reproducing Empire, 102.
  11. James A. Miller,“Betting with Lives : Clarence Gamble and the Pathfinder International,” Population Research Institute, July 1, 1996,
  12. Briggs, *Reproducing Empire*, 102-107; Sarah Zhang, A Long-Lost Data Trove Uncovers California’s Sterilization Program,” The Atlantic, January 3, 2017,
  13. C.J. Gamble, “Spermicidal Times as Aids to the Clinician’s Choice of Contraceptive Materials,” Fertility and Sterility 8, no. 2 (1957): 174–84; Briggs, Reproducing Empire, 102-3.
  14. Briggs, Reproducing Empire, 107.
  15. Pendergrass and Raji, “The Bitter Pill.”
  16. Pendergrass and Raji, “The Bitter Pill.”
  17. Pendergrass and Raji, “The Bitter Pill.”
  18. Briggs, Reproducing Empire, 131.
  19. Pendergrass and Raji, “The Bitter Pill.”
  20. Briggs, Reproducing Empire, 136.
  21. Briggs, Reproducing Empire, 135-136.
  22. Briggs, Reproducing Empire, 136-137.
  23. Briggs, Reproducing Empire, 137.
  24. Briggs, Reproducing Empire, 137-139.
  25. Pendergrass and Raji, “The Bitter Pill;” PBS, “The Puerto Rico Pill Trials,” The American Experience, 2019,
  26. García, Ana María, La operación, film, directed by Ana María García, Puerto Rico: Latin America an Film Project, 1982.
  27. PBS, “The Puerto Rico Pill Trials;” Planned Parenthood Federation of America, “The Birth Control Pill, A History,” last updated June 2015.
  28. Pendergrass and Raji, “The Bitter Pill.”
  29. García, “La operación.”
  30. US Congress, Senate, Puerto Rico Oversight, Management, and Economic Stability Act, Public Law 114-187, U.S. Statutes at Large 549 (2016): 2328.