The Environment International study of 36.6 million summer births (1979-2019) across 250 cities in 13 countries is a large-scale observational analysis, not an RCT, with no reported conflicts of interest disclosed by authors Royé, Vicedo-Cabrera and colleagues. It finds linear heat-related preterm risk rises of 2.8-3.8 percent, equating to 855 attributable cases per million births, yet understates how urban heat islands and occupational exposure cluster among low-SES groups, amplifying effects beyond the reported non-significant subgroup trends. Cross-referencing with Chersich et al. (Lancet Planetary Health, 2020; systematic review of 70 studies) and the 2023 IPCC AR6 health chapter reveals that heat accelerates both preterm and term deliveries via thermoregulatory stress and inflammatory pathways, a mechanism the original coverage omits. Disparities peak in Paraguay (1,347 excess cases per million) versus Switzerland (628), underscoring adaptation gaps that parallel malaria burdens in LMICs. Long-term population consequences include elevated lifetime cardiovascular and neurodevelopmental risks for exposed cohorts, an under-covered intergenerational burden that demands integration into climate-health adaptation models.