PIGF and fetal growth restriction: In recent collaborations between the BiB cohort and the Pregnancy Outcome Prediction study (POPs) using Metabolon MS data, we have found evidence that 4’-hydroxyglutamate improves prediction of pre-eclampsia compared to clinical risk factors alone3 and that a ratio of four metabolites (1-(1-enyl-stearoyl)-2-oleoyl-GPC, 1,5-anhydroglucitol,5α-androstan-3α,17α-diol disulfate and N1,N12-diacetylspermine) together with the sFlt-1:PIGFratio is a better predictor of fetal growth restriction/small for gestational age than sFlt-1:PIGF alone4.