By the end of the 19th century, the medical specialties of gynecology and obstetrics established a new trend in women’s healthcare. In the 20th century, more and more American mothers gave birth under the care of a university-trained physician. The transition from laboring and delivering with the assistance of female family, neighbors, and midwives to giving birth under medical supervision is one of the most defining shifts in the history of childbirth. By the 1940s, the majority of American mothers no longer expected to give birth at home, but instead traveled to hospitals, where they sought reassurance from medical experts as well as access to pain-relieving drugs and life-saving technologies. Infant feeding followed a similar trajectory. Traditionally, infant feeding in the West had been synonymous with breastfeeding, although alternatives such as wet nursing and the use of animal milks and broths had existed as well. By the early 20th century, the experiences of women changed in relation to sweeping historical shifts in immigration, urbanization, and industrialization, and so too did their abilities and interests in breastfeeding. Scientific study of infant feeding yielded increasingly safer substitutes for breastfeeding, and by the 1960s fewer than 1 in 5 mothers breastfed. In the 1940s and 1950s, however, mothers began to organize and to resist the medical management of childbirth and infant feeding. The formation of childbirth education groups helped spread information about natural childbirth methods and the first dedicated breastfeeding support organization, La Leche League, formed in 1956. By the 1970s, the trend toward medicalized childbirth and infant feeding that had defined the first half of the century was in significant flux. By the end of the 20th century, efforts to harmonize women’s interests in more “natural” motherhood experiences with the existing medical system led to renewed interest in midwifery, home birth, and birth centers. Despite the cultural shift in favor of fewer medical interventions, rates of cesarean sections climbed to new heights by the end of the 1990s. Similarly, although pressures on mothers to breastfeed mounted by the end of the century, the practice itself increasingly relied upon the use of technologies such as the breast pump. By the close of the century, women’s agency in pursuing more natural options proceeded in tension with the technological, social, medical, and political systems that continued to shape their options.