Abstract
We study the determinants of season of birth of the first child, for White non-Hispanic married women aged 25-45 in the US, using birth certificate and Census data. The prevalence of good season (quarters 2 and 3) is significantly related to mother’s age, education, and smoking status during pregnancy, as well as to receiving WIC food during pregnancy and to pre-pregnancy body mass index. Moreover, those who did not use assisted reproductive technology (ART) present a higher prevalence of good season births. The frequency of good season is also higher and more strongly related to mother’s age in states where cold weather is more severe, and varies with mother’s occupation, exhibiting a particularly strong positive association with work-ing in “education, training, and library”. Remarkably, this relationship between good season and weather disappears for mothers in “education, training, and library” oc-cupations, revealing that season of birth is a matter of choice and preferences, not simply a biological mechanism. We estimate the compensating wage differential for mothers who work in jobs other than “education, training, and library”, which allows us to provide an upper-bound to the life-time value of good season of birth of about USD 1,000,000. Finally, we present evidence that good season of birth is positively related to health at birth conditional on several maternal characteristics.