The Fertility and Families Surveys (FFS) were conducted in the 1990s across 23 member States of the United Nations Economic Commission for Europe (UNECE). The project concluded in 2000 and it is the direct predecessor to the GGS. The datasets are highly comparable with GGS data and are available to registered researchers.
Find more about the FFS on the UNECE website here.
The datasets can be downloaded from the GGP Data Portal.