The aim of this large, case–control study to examine whether four previously validated24 type 2 diabetes- and cardiovascular disease-associated serum ceramides Cer(d18:1/16:0), Cer(d18:1/18:0), Cer(d18:1/24:0) and Cer(d18:1/24:1) and the Cer(d18:1/18:0)/Cer(d18:1/16:0) ratio, as well as traditional lipids, measured in early pregnancy, are predictors of subsequent GDM. The gene discussed is CBLN1; the disease is type 2 diabetes mellitus.