“…A burgeoning literature has identified adverse short-term impacts of extreme temperatures on several population outcomes, including elderly mortality (Deschênes and Moretti, 2009;Deschênes and Greenstone, 2011), emergency department visits and hospitalizations (Green et al, 2010;White, 2017), and cognitive performance (Cho, 2017;Garg et al, 2018;Goodman et al, 2018;Graff Zivin, Hsiang, and Neidell, 2018). Further, two recent studies have shown that in utero heat exposure has lasting negative effects on long-term cognitive ability (Hu and Li, 2019) and adult earnings (Isen, Rossin-Slater, and Walker, 2017), highlighting the sensitivity of the prenatal period to extreme heat. 2 To the best of our knowledge, however, no prior studies have identified the causal effects of prenatal exposure to extreme temperatures on the health of the mothers themselves, and this paper aims to fill this gap.…”