This article examines the construction of parenthood, drawing on Brazilian cisgender, heterosexual, and homosexual couples' experiences in using assisted reproduction technologies (ART), particularly the surrogacy. For that purpose, we interviewed: 1) a lesbian woman who had her daughter through her partner's pregnancy, using ART with anonymous donor semen; 2) a gay man who, together with his partner, used a surrogacy service under contract via a specialised offshore agency; 3) a woman who was a surrogate, in Brazil, for her sister-in-law and brother who lived abroad and, from abroad, sent an embryo fertilised for surrogacy; 4) a woman who resorted to her sister-in-law in order to be a mother by surrogacy, with ovules from the woman herself fertilised with semen from her husband; and 5) the sister-in-law mentioned in 4), who acted as surrogate for her brother and his wife. These interviews made it possible to think about the discursive construction of the legitimacy of such parenthoods, as it is produced by access to, and manipulation and circulation of, reproductive technologies and persons. This biomedical management of bodies sets up a material and discursive circuit that, in turn, produces a complex web of personal, normative, legal, professional and market relationships, particularly with a view to construction of a parenthood anchored in a notion of biologically-constituted origin. In this respect, biological, affective and social bonds merge to produce a precise placement of who is the father and/or who is the mother, as well as who are the important others and how they are linked to the child in a broader web of parenthood.