Abstract. Recent science and technology studies (STS) debates on valuation mechanisms have highlighted how social, ethical, and political values are embedded in scientific and technological practices—particularly through regulation and market design. In this context, scholars working on assisted reproductive technologies (ART) have examined how bodies, tissues, and reproductive labor are integrated into market economies structured by transnational inequalities and postcolonial legacies. Using a feminist political economy lens, this article advances STS discussions by analyzing how state-enforced quality standards and altruistic narratives function as valuation mechanisms in the reproductive bioeconomies of Ukraine and Spain. These mechanisms not only shape the valuation of ova but also reproduce economic hierarchies, gendered and racialized labor stratification, and core–periphery dependencies within global reproductive value chains. Drawing on qualitative data, we examine how regulatory differences influence each country's role in European ART markets. Ukraine's permissive regulatory environment and lack of EU alignment allow for competitive pricing but raise concerns about quality standards, reinforcing its position as a peripheral, low-cost supplier. In contrast, Spain's regulated ART sector, aligned with EU standards, generates higher ova value through trust and credibility, solidifying its position within the “core.” This article argues that valuation processes are co-constructed through regulation, technologies, and market economies, legitimizing reproductive markets while obscuring underlying structural inequalities.