Many of the changes taking place in American life reflected the fact that the role of women was in a state of rapid transition. In the years immediately following the war, many women gave up their jobs in factories and returned to their traditional role as homemakers, sparking the “baby boom” of the late 1940s and 1950s. Eventually, however, many women became restive with their restrictive role as wives and mothers and began to enter the workforce at an increasing rate. Unlike the situation before World War II, many of them were married. In 1900, for example, married women made up about 15 percent of the female labor force. By 1970, their number had increased to 62 percent. As in Europe, however, American women were still not receiving equal treatment in the workplace, and by the late 1960s, some began to assert their rights and speak as feminists. Leading advocates of women’s rights in the United States were Betty Friedan and Gloria Steinem. A journalist and the mother of three children, Friedan (b. 1921) grew increasingly uneasy with her attempt to fulfill the traditional role of housewife and mother. In 1963, she published The Feminine Mystique, in which she analyzed the problems of middle-class women in the 1950s and argued that women were systematically being denied equality with men. The Feminine Mystique became a best-seller and transformed Friedan into a prominent spokeswoman for women’s rights in the United States. As women became more actively involved in public issues, their role in education increased as well. Beginning in the 1980s, women’s studies programs began to proliferate on college campuses throughout the United States. Women also became active in promoting women’s rights in countries around the world, and they helped organize international conferences on the subject in Mexico City, Copenhagen, Nairobi, and Beijing.