This paper proposes a new mechanism linking technology, the gender gap in education, and fertility in a growth model in order to explain the long run transition from stagnation to modern sustained growth, through the demographic transition, and the accompanying improvements in gender equality in education and income. The mechanism includes three main components. First, increases in the level of technology not only increase the return to human capital but also reduce women's time in doing housework, leaving women with more time for child care and labor-force participation, since technological progress creates labour-saving products for doing housework. Second, the decreases in women's time devoted to housework in the future make households today invest relatively less in education for their sons in order to invest more in education for their daughters because the marginal return to female education is higher than that to male education, therefore, improving the gender equality in education. Third, the better gender equality in education, in turn, accelerates the technological progress. This positive feedback loop generates a demographic transition accompanied with accelerated economic growth.