The set of periodic orbits of a non-singular Morse-Smale (NMS) flow on
S-3 defines a link; a characterization of all possible links of NMS f
lows on S-3 has been developed by Wada. In the frame of codimension-on
e bifurcations, this characterization allows us to study the restricti
ons a link requires for suffering a given bifurcation. We also derive
the topological description of the new link and the possibility of rel
ating links by a chain of this type of bifurcation.