Civil law jurisdictions have more than others effectively resisted the commodification of gestation capacities, relying on the old Roman aphorism mater semper certa est (‘it is always certain who the mother is’). Faced with the complexities of stratified reproduction [Anagnost, A., 2004. Maternal labor in transnational circuits. In: J. S. Taylor, L. L. Layne, and D. F. Wozniak, eds. Consuming motherhood. New Brunswick, NJ: Rutgers University Press, 139–167], the mater semper certa est rule allows for the birth mother to be considered as the legal mother. Thus, the gestational model of motherhood, that rules in countries such as Spain, France, and Italy, acts as a deterrent against prospective parents’ entering into a surrogacy contract, both domestically as well as at the international level.

This paper offers a vindication of the Roman aphorism as a fair principle to protect birth mothers and their children from the abuses of reproductive market forces.

大陆法司法管辖区比其他司法管辖区更有效地抵制妊娠能力的商品化，依靠古老的罗马格言mater semper certa est（“母亲是谁总是确定的”）。面对分层再生产的复杂性 [Anagnost, A., 2004。跨国循环中的母体劳动。在：JS Taylor、LL Layne 和 DF Wozniak，编辑。消费母性。新泽西州新不伦瑞克：罗格斯大学出版社，139–167]，该材料已确定规则允许将生母视为合法母亲。因此，在西班牙、法国和意大利等国家规定的孕产模式在国内和国际层面对准父母签订代孕合同起到了威慑作用。

本文证明了罗马格言是保护生母及其子女免受生殖市场力量滥用的公平原则。