Aim: Small for gestational age neonates (SGA) could be subdivided into two groups according to the underlying causes leading to low birth weight. Intrauterine growth restriction (IUGR) is a pathologic condition with diminished growth velocity and fetal compromised well-being, while non-growth restricted SGA neonates are constitutionally (genetically determined) small. Antenatal sonographic measurements are used to differentiate these two subgroups. Maternal metabolic changes contribute to the pathogenesis of IUGR. A disturbed lipid metabolism and cholesterol supply might affect the fetus, with consequences for fetal programming of cardiovascular diseases. We evaluated fetal serum lipids and hypothesized a more atherogenic lipoprotein profile in IUGR fetuses.
Methods: Umbilical cord serum lipids and oxidative modified, low-density lipoprotein (oxLDL) concentrations were measured by colorimetric enzymatic measurements, or by ELISA. Values of IUGR (n=36) and constitutionally small for gestational age neonates (SGA, n=22) were compared with those of healthy, adequate for gestational age, born neonates (CN, n=97). SAS-statistic software was used and two-way ANOVA was adjusted for gestational age at delivery.
Results: Fetal high-density lipoprotein cholesterol (HDL-C) and total cholesterol (TC) concentrations were found to be lower in the IUGR compared to the CN and SGA groups (HDL-C: P<0.001, TC: P<0.01). Atherogenic indices, including the oxLDL/LDL-C ratio, were increased in the IUGR compared to the CN group (oxLDL/LDL-C ratio: P<0.001).
Conclusion: Our results support the hypothesis of a disturbed cholesterol supply in IUGR fetuses. Born SGA has been shown to be a risk factor for developing cardiovascular disease later in life. Since HDL-C has anti-inflammatory properties, a reduced HDL-C during fetal development, and an increase in atherogenic indices, might provide a link to this observation in IUGR fetuses.