INTRODUCTION: There is limited epidemiologic evidence on the associations between ambient temperature and early outcomes of in vitro fertilization (IVF). This study examined the association between ambient temperature exposures during spermatogenesis in males and folliculogenesis in females with early IVF outcomes. METHODS: This retrospective cohort study included 529 oocyte donors linked to male partners of 1154 recipient couples who underwent 1379 oocyte thaw cycles between 2008 and 2020 at an IVF clinic in Atlanta, Georgia, USA. Daily ambient mean (T RESULTS: Higher ambient temperature exposures during folliculogenesis and ovarian stimulation generally had negative, though imprecise, associations with oocyte yield (% change in total oocytes retrieved per IQR increase in mean temperature = -6.9% 95% CI -18.5,6.3). Higher temperature exposures during folliculogenesis (aOR = 1.85 95% CI 1.16, 2.95) and ovarian stimulation (aOR = 2.14 95% CI 1.44, 3.19) were associated with higher oocyte survival and higher T CONCLUSIONS: Higher ambient temperature exposure during follicular development was positively associated with oocyte survival and fertilization. These findings highlight the reproductive health implications of increasing global average temperatures, though more research is needed to clarify these associations.