During the medieval and Golden Age eras, analogies to women’s reproductive capacities played a prevalent role in shaping material, literary, and political frameworks. Maternal Structures delves into how Iberian writers and artists framed their work using gynocentric symbols while engaging with fundamental theological theories around conception and the emergent discipline of medicine. This work shows how newly accessible medical treatises in the thirteenth century and their subsequent evolution until the seventeenth century understood maternity and brought about an ideological shift in the way premodern authors structured and outlined their written work. Maternal Structures traces how the genesis and construction of modern authorship were closely dependent on the use of maternal imageries to illustrate the underlying processes of intellectual (re)production. The idea of original writing in the premodern period as a maternal attribute not only meant higher usage of maternal figurations but also altered the structure of produced texts by utilizing the framing device to give their literary creations a more tangible body. Maternal Structures contends that the stylistic authorial choice of employing a framing device comes with an underlying biological subtext in the author’s mind by transforming it into a narrative womb. Because this narrative womb is often comprised of a heavy authorial presence, the author himself becomes the structure that holds the embedded stories and delivers them to their reader. The initial chapter discusses how King Alfonso X strategically utilized the Virgin Mary as a rhetorical tool to establish himself as a divine representative and maternal figure who birthed his Cantigas de Santa María. Shifting focus from birthing to nursing, the second chapter delves further into the symbolic depiction of the breast and its role in transmitting the medical wisdom Alfonso X provided the kingdom thanks to the patronage of the Toledan school of translators. The third chapter examines Don Juan Manuel’s Conde Lucanor, tracking a shift from a feminine to a male framing device, which reflects changes in theological ideals and knowledge transfer from female midwives to male physicians. The final chapter explores María de Zayas’ two volumes of novelas for analogies between biological reproduction and literary creation that challenge patriarchal structures while reclaiming women’s labor in midwifery and intellectual creativity. Maternal Structures sheds light on intricate dynamics at play within gendered authority structures during these periods of multiconfessional literary production and scientific renaissance.