FreeCAD drawings (.fcstd) can be exported by the program to all kinds of other 3D data, including IGES format (.igs, .iges). Unfortunately, we do not know about any program that can perform this CAD conversion as .fcstd files seems to be exclusive to FreeCAD.
Open FCSTD file Open IGS fileAn open source multiplatform 3D CAD/MCAD/CAx/CAE/PLM modeler