Beyond the Natural Body shows that the power to control sex and the body is embodied not only in scientific theory, but also in materialities. This is why I suggested that it is crucial for feminist studies of science to take into account this materiality of the scientific enterprise. The suggestion that science is primarily texts and theories seriously fails to take into account the strongest tools that scientists have at hand to transform and sexualize the world we live in: the creation of material products. A focus on the materiality of science shows how the construction of meanings and practices of sex and the body is not restricted to the domain of theories and semiotics.

In the first place, sex endocrinology produced new diagnostic techniques. The use of tests introduced for measuring hormones in animals did not remain restricted to the laboratory. Clinicians, particularly gynecologists, transferred the laboratory tests to the clinic as tools for the diagnosis of hormonal deficiences. Laboratory scientists introduced three types of tests: the sex hormone blood test (one to estimate male sex hormones, one to estimate female sex hormones), the pregnancy test and the vaginal smear test. Clinicians used the sex hormone blood test to measure the sex of homosexual men and to classify women into hormonal types. The female sex hormone blood test was also used for the diagnosis of menstrual disorders and pregnancy. The pregnancy test became widely used as the first laboratory test for the early diagnosis of pregnancy. The introduction of the vaginal smear test provided gynecologists and physicians with a powerful new diagnostic tool to investigate their female patients. They have used this test for the diagnosis of menstrual disorders, and more recently for the diagnosis of cancer. The introduction of this test profoundly shaped the medical treatment of the female body, extending medical intervention techniques from the uterus and the ovaries to the vagina.

In addition to the introduction of diagnostic techniques, sex endocrinology provided the medical profession with a new class of drugs that were developed to cure a newly constructed category of diseases: hormone deficiency diseases. Sex endocrinologists defined low levels of hormones as deficiencies. In this manner, they transformed the hormonal model of sex into a model of disorders and pathologies. The concept of hormonal deficiency disease implies that this category of diseases can be treated with the administration of hormones to make up for the lack of these substances. I described how this hormonal model of diseases became integrated into medical practice. The introduction of hormones as drugs had a major impact on medical practice, particularly on women, since it was the female body that became increasingly subjected to medical intervention. The specification of the hormone model of the female body as cyclic in nature further facilitated the process of classifying women’s diseases in terms of deficiencies that could be treated with hormones. The introduction of the pill, last but not least, revolutionalized sexual experiences by providing a means to separate sexuality from reproduction.

The introduction of the concept of sex hormones not only changed the medical treatment of the human body, but also redefined the existing social configurations structuring medical practice. The story about hormones thus becomes a story about power and medicine. The field of sex endocrinology generated a set of power relations that did not exist prior to its emergence. What changed in this period was the question of who was entitled to claim authoritative knowledge about the female body. The introduction of the hormonal model increased the medical authority of gynecologists over disorders traditionally belonging to other medical professions, such as psychiatry. The hormonal model thus enabled gynecologists to draw the female body more and more deeply into the gynecological clinic. Gynecologists, however, had to share their increased medical authority with another professional group: the laboratory scientists. With the introduction of the concept of sex hormones, scientists explicitly linked women’s diseases with laboratory practice. Laboratory scientists entered a field until then relatively untouched by laboratory science. Before the turn of the century, the study of women’s diseases, traditionally ascribed to dysfunction of the ovaries, was the exclusive field of gynecologists. In the decades to follow, research on the ovaries shifted from the clinic to the laboratory. Laboratory scientists succeeded in becoming experts on disorders in the ovaries and female reproduction. In this manner, laboratory scientists gained a new realm of influence, claiming authoritative knowledge over a subject previously allocated to gynecologists. The gynecologists thus lost their position as the sole experts on women’s diseases and reproduction.

This story of hormones is a story of multiple and mobile power relations, very similar to Foucault’s accounts of power (Foucault 1975; 1976). Here power is not a fixed, homogeneous thing, located in one specific place or institution, neither is it possessed by one specific actor. My account of the history of sex hormones shows the dynamic, capillary power of a science which linked cultural assumptions, concepts, ovaries, urine, diagnostic tests, lab equipment, marketing strategies, clinical trials, population policies and bodies, thus transforming the world we live in. Beyond the Natural Body shows the enormous transformative power of biomedicine: a world with hormones looks quite different from a world without them. Sex hormones shaped our understanding of sex and the body, they changed the medical treatment of our bodies, they constituted a new specialty in the biomedical sciences, they thoroughly changed the cultural and material authority of the laboratory and the clinic, and last but not least, sex hormones redefined the relationship of women to reproduction.