Autodesk Inventor supports IGES/IGS format just fine so you should have no trouble opening *.igs files in it and use them for making *.ipt part files. Other CAD programs with support of Inventor's formats can be probably used the very same way.
Convert IGES 3D exchange format to AutoDesk Inventor CAD part.
We found 2 software records in the database related to .igs to .ipt file format conversion.
Microsoft Windows software - convert igs to ipt on Windows
Autodesk Inventor is modeling application used to create 3D digital prototypes.
Convert from igs file format
The tables with software actions are a good pointer for what a certain program does with various file types and often may give users a good hint how to perform certain file conversion, for example the above-mentioned igs to ipt. However, it is not perfect and sometimes can show results which are not really usable because of how certain programs work with files and the possible conversion is thus actually not possible at all.
A 2D and 3D CAD construction software