c-peptide and Fetal-Distress

Insulin-like growth factor-binding protein-1 (IGFBP-1) is believed to be an inhibitory factor for fetal growth. The regulation of IGFBP-1 secretion in the fetus is uncertain, although insulin and oxygen tension (PO2) and saturation are thought to play a role. We studied IGFBP-1 levels in umbilical cord artery (UA) and vein (UV) of 98 singleton fetuses at term with clinical signs of distress during labor, i.e. meconium-stained liquor or/and an abnormal fetal heart rate tracing. Blood gas values and serum C-peptide and IGFBP-1 concentrations were measured in both UA and UV. Twenty-five fetuses had an UA pH<7.20. The concentrations of IGFBP-1 were similar in UA and UV and were highly correlated (r=0.98). IGFBP-1 levels were inversely correlated with birth weight, with increased concentrations in small-for-gestational age fetuses (< or =10th weight percentile). IGFBP-1 levels were negatively correlated with C-peptide concentrations, and remained so after correction for birth weight (r=-0.37 for both UA and UV; P<0.001); more specifically, IGFBP-1 levels were increased in the lowest C-peptide quartile (<0.23 nmol/l) compared with the other quartiles. In addition, IGFBP-1 levels were inversely correlated with PO(2) values (r=-0.39 in UA and r=-0.34 in UV; P<0.001); quartiles of UA and UV PO2 showed a gradual increase in IGFBP-1 concentrations with lower PO2 values. A regression model with C-peptide and PO2 values as independent variables predicted IGFBP-1 concentrations (R2 of model was 0.25 and 0.22 for UA and UV respectively; P<0.001). Other blood gas values (pH, PCO2, HCO3- and base deficit) did not correlate with IGFBP-1 levels. The data of this study indicate that serum IGFBP-1 levels in term fetuses are determined by both insulin and PO2 levels, and suggest that acute hypoxemia stimulates IGFBP-1 secretion in the fetus.

Topics: Analysis of Variance; Birth Weight; C-Peptide; Female; Fetal Distress; Humans; Insulin-Like Growth Factor Binding Protein 1; Obstetric Labor Complications; Oxygen; Partial Pressure; Pregnancy; Umbilical Arteries; Umbilical Veins

Umbilical cord plasmatic levels of insulin, peptido-C and glucagon in two groups of normal and stressed newborns, in the first and third days of life and were measured and compared with those of their mothers. The levels of insulin were significantly higher in normal newborns (p less than 0.001) than in their mothers but not significant with those found in the stressed newborn. After three days of life the mean values on insuline were 14.67 +/- 7.2, without significant differences with the other two groups. The mean values of peptido-C were not significantly different in the three groups. The molar relation in every case was higher than 1. The levels of glucagon in umbilical cord of normal newborn were 196.42 +/- 51.45 with significant elevation (p less than 0.05) after three days of life. In stressed newborn group the values in umbilical cord were significantly higher (p less than 0.01) than the foud values in normal newborn.

Topics: C-Peptide; Female; Fetal Blood; Fetal Distress; Glucagon; Glucose; Humans; Infant, Newborn; Insulin; Labor, Obstetric; Maternal-Fetal Exchange; Pregnancy