This paper discusses how two theoretical frameworks from the STS field (co-production and critical realism) can help understand the dynamics of policy development with emerging technologies. The point of departure of this paper is the comparison of the inscription of two emerging technologies in public health sectors. The NIPT (non invasive prenatal testing) for pregnant women very recently developed in many countries, for the detection of foetus anomalities based of the analysis of the mother’s blood (Fallon 2017). At the same time new methods for save medicated abortion are made availbale thanks to internet in all countries. The development of these emerging technologies can be followed through analysing the investments of professionals of the health sector, with public administrations, and with emerging demands from the enduser) : I use these innovations as examples of co-construction of new patterns of “social orders” (Jasanoff 2004,2005) and technologies which followed very diverse trajectories of inscriptions in the local public health systems. The fieldwork was organised to “follow the actors and the objects”, with a comparative interpretative methodology of science/politics relations (analysing framings, boundaries, institutional discourses, actors identities): it helped understand the close and parallel development of technico-scientific and socio-political changes simultaneously. The comparative approaches (of these technologies within two different countries) highlights the importance to complement the co-productionist approach by integrating specific national modes of production and valuation of scientific knowledge and technological innovations (Tyfield 2012). The same techniques and knowledge are available in both countries, whether for prenatal screening or medical abortion, but the political and policy frameworks are very different in both countries. The medical public programs provide "emancipatory" follow-up for Belgian couples during pregnancy. In Argentina, where the use of legal abortion is ...