FGFR1 and fetal growth restriction: Furthermore, the expression of sodium dependent phosphate transporter SLC20A2 mRNA was lower in caruncles from CSH RNAi IUGR compared to CSH RNAi Non-IUGR pregnancies, and this was accompanied by the lower expression of mRNAs for components of the KL-FGF signaling cascade (KL, FGFR1, and FGFR2) in cotyledons from CSH RNAi IUGR pregnancies compared to Control RNAi and/or CSH RNAi Non-IUGR pregnancies.