Karen Oppenheim Mason was an American sociologist and demographer. She served as president of the Population Association of America in 1997^[1][2] and was best known for her research on the relationship between changes in fertility patterns and social changes in gender roles.^[3][4][5]

Mason grew up in a poor family in New York and attended Reed College on a scholarship, majoring in Sociology.^[2] Mason earned her Ph.D. in sociology at the University of Chicago in 1968. She became a demographer while working in her first faculty position in the Department of Sociology at the University of Wisconsin.^[2]

After teaching at the University of Wisconsin for three years, Mason took a job at the Research Triangle Institute doing research on women's labor force participation in the Research Triangle area of North Carolina.^[2] In 1973, Mason moved to the University of Michigan, where she became a Professor of Sociology and Associate Director of the Population Studies Center. She taught graduate courses on gender and undergraduate courses on the family.^[2] In 1980, Mason held a fellowship at the Center for Advanced Study in the Behavioral Sciences at Stanford University.^[6]

Through her research, Mason applied quantitative analysis to gender theory and gender theory to demography.^[2] In the second half of the twentieth century, birth rates were a central concern of demographers, who uncritically attributed fertility to women.^[7] Mason was among the first demographers to use gender theory to explain fertility trends, and to recognize the relationship between gender dynamics and fertility rates.^[3][4][5] Mason served as President of the Population Association of America in 1997.^[1][2] She devoted her presidential address to improving demographic understandings of fertility transition (long-term declines in average family size) by taking a perceptual, interactive approach.^[8]

Mason left the University of Michigan in 1991, first becoming Director of the Population Studies Program at the University of Hawai'i and of the Program on Population at the East-West Center, and then becoming Director of the Gender and Development Program at the World Bank in Washington, DC. She retired from this position in 2004.^[2]

• Karen Oppenheim Mason. 1986. "The Status of Women: Conceptual and Methodological Issues in Demographic Studies." Sociological Forum 1(2): 284–300. DOI 10.1007/BF01115740.
• Karen Oppenheim Mason. 1987. "The Impact of Women's Social Position on Fertility in Developing Countries." Sociological Forum 2(4): 718–745. DOI 10.1007/BF01124382.
• Karen Oppenheim Mason and Anju Malhotra Taj. 1987. "Differences between Women's and Men's Reproductive Goals in Developing Countries." Population and Development Review 13(4): 611–638. DOI 10.2307/1973025.
• Karen Oppenheim Mason and Yu-Hsia Lu. 1988. "Attitudes Toward Women's Familial Roles: Changes in the United States, 1977–1985." Gender & Society 2(1): 39–57. DOI 10.1177/089124388002001004.
• Karen Oppenheim Mason and An-Magritt Jensen. 1995. Gender and Family Change in Industrialized Countries. New York: Oxford University Press. ISBN 0-19-828970-7.
• Karen Oppenheim Mason. 1997. "Explaining Fertility Transitions." Demography 34(4): 443–454. DOI 10.2307/3038299.
• Karen Oppenheim Mason. 2001. "Gender and Family Systems in the Fertility Transition." Population and Development Review 27(Supplement): 160–176. jstor.org/stable/3115254.