The effect of ambient temperature shocks during conception and early pregnancy on later life outcomes

A large body of research has recently shown that early life or in utero shocks, especially climatic shocks, may a ect long-run human capital outcomes. Most of these e ects are assumed to be biological including poor nutrition during critical windows of fetal development, or through increased maternal stress. However, in addition to these biological e ects, climatic conditions at the time of conception may also cause changes in parental behavior, not only a ecting the mix of parents who conceive, but also the characteristics of the children once born. This paper explores whether increases in ambient temperature at the time of conception, while in utero, or after birth cause better educational and health outcomes as adults. Using Census and Demographic and Health Survey data from sub-Saharan Africa, we show that individuals conceived during high temperatures have higher educational attainment and literacy. In addition, we nd evidence of temperature Corresponding author. Email: [email protected]. Mailing address: University of South Florida, 4202 East Fowler Avenue, CMC 342, Tampa, FL 33620, USA. Tel.: 813-974-2076. Fax: 813-974-6510. Email: [email protected]. Paris School of Economics CNRS, 48 Boulevard Jourdan, 75014 Paris, France. Email: [email protected]. AT&T, 1120 20th St. NW., Washington DC., 20036, USA. Research was completed before author began employment at AT&T. e ects at other times in utero, especially during the rst trimester. We then explore the biological and behavioral mechanisms through which this e ect may occur, including heat-induced changes in sexual behavior, di erences in parental characteristics, and intensi ed fetal selection. We conclude that fetal selection is the most likely mechanism driving our result. We also show that temperature deviations change the mix of conceiving women to be wealthier, partly since heat-induced reductions in sexual activity are larger for poorer women. JEL Codes: I12, I15, J13, O15.