INSULIN-LIKE-GROWTH-FACTOR-I IN FETAL SERUM OBTAINED BY CORDOCENTESISIS CORRELATED WITH INTRAUTERINE GROWTH-RETARDATION

We examined whether insulin-like growth factor-I (IGF-I) and one of it s binding proteins (IGFBP-1) in fetal serum obtained by cordocentesis is correlated with intrauterine growth retardation (IUGR) and weight e stimation by ultrasound. Cordocentesis sera from 27 fetuses suspected of having IUGR were analysed for IGF-I and IGPBP-1 by radioimmunoassay , The results showed that IGF-I concentrations were correlated signifi cantly with birth weight (P < 0.001) and placenta weight (P < 0.05). M ean fetal concentrations of IGF-I were 38 +/- 18 mu g/l. In patients ( n = 11) with a weight deviation at delivery <-33%, IGF-I concentration s were 24.1 +/- 13.2 mu g/l. IGFBP-1 was inversely correlated with bir th weight (P < 0.006) and concentrations of IGF-I. Mean plasma concent rations of IGFBP-1 were 234.2 +/- 161.4 mu g/l. Furthermore, IGF-I con centrations were correlated with the weight deviation estimated by ult rasonography at the time of cordocentesis (P < 0.007), as well as with the weight deviation at delivery (P < 0.0001). The actual weight devi ation at delivery was correlated more strongly with fetal IGF-I concen trations than with the estimated weight deviation at cordocentesis. Th e lowest concentrations of IGF-I mere found in patients with a weight deviation <-33%, Very low concentrations of IGF-I are thus associated with IUGR, indicating that IGF-I measured in fetal serum may increase the predictive value of ultrasonographic weight estimation.