The copper intrauterine device, or IUD, is a long-term, reversible contraceptive first introduced by Howard Tatum and Jamie Zipper in 1967. Health care providers place an IUD inside a woman’s uterus to prevent pregnancy. Copper IUDs are typically made of T-shaped plastic with some portion covered with exposed copper. Prior to the invention of the first IUDs, women had few long-term options for safe and reliable birth control. Those options mostly consisted of barrier methods and the oral birth control pill, which were only effective if used correctly and consistently. For women seeking to control their fertility, a copper IUD was one of the first forms of long-term birth control that was highly effective and did not require consistent and regular action on the woman’s part to remain effective.

The Chicago Women’s Liberation Union, hereafter Union or CWLU, was a feminist union that operated in Chicago, Illinois, from 1969 to 1977 and was the first and largest union, at the time of its operation, focused on women’s issues. The Union organized women with the self-proclaimed collective goal of achieving liberation from sexism and inequality. Within the larger CWLU, smaller groups and chapters formed to address issues such as abortion, rape, child care, and reproductive health, among others. During CWLU’s eight years of operation, the activists circulated petitions, held demonstrations, and visited high schools to raise public awareness of women’s issues. The CWLU created educational opportunities for women in response to apparent sexism in the US and connected them to social groups to further the women’s liberation movement and women’s reproductive health awareness in the United States.

In 2012, Stephen Sidney, T. Craig Cheetham, Frederick A. Connell, and colleagues published “Recent Combined Hormonal Contraceptives (CHCs) and the Risk of Thromboembolism and Other Cardiovascular Events in New Users,” hereafter “Combined Hormonal Contraceptives” in Contraception. The authors gathered records of major cardiovascular events in patients who were using combined hormonal contraceptive treatments, or CHCs. A CHC is a birth control medication that contains both estrogen and progestin hormones. The CHCs of focus, which the authors referred to as the study CHCs, included a pill, patch, and vaginal ring that the US Food and Drug Administration, or FDA, recently approved at the time of publication. The researchers compared the rates of cardiovascular events between users of the study CHCs to users of established CHCs to find any increased cardiovascular risk. “Combined Hormonal Contraceptives” showed that the study CHCs did come with some increased cardiovascular risk, and reconfirmed the known cardiovascular risks of CHCs in general, providing safety information for people who may want to start birth control.