Relationship of insulin-like growth factor-I and insulin-like growth factor binding proteins in umbilical cord plasma to preeclampsia and infant birth weight.
OBJECTIVE
To determine whether preeclampsia influences insulin-like growth factor-I (IGF-I), insulin-like growth factor binding protein-1 (IGFBP-1), and insulin-like growth factor binding protein-3 (IGFBP-3), independent of its effect on birth weight.


METHODS
Cord blood was collected in 12,804 consecutive deliveries. We identified 258 preeclamptic pregnancies that were subclassified as mild or severe and early or late. For comparison, 609 control pregnancies were selected. Fetal growth was expressed as the ratio between observed and expected birth weight, with adjustment for gestational age at birth. IGF-I, IGFBP-1, and IGFBP-3 were measured in umbilical plasma. The contribution of preeclampsia and birth weight to each measured factor was assessed by multiple linear regression analyses.


RESULTS
Between mild preeclampsia and controls, there were no differences in IGF-I, IGFBP-1, and IGFBP-3. In severe and early onset preeclampsia, umbilical cord plasma IGF-I was approximately 50% lower, and IGFBP-1 was more than twice as high as in controls (both P <.01). At each birth weight level, IGF-I was lower and IGFBP-1 was higher in severe or early preeclampsia than among controls of similar weight. Birth weight and preeclampsia were, independent of each other, associated with IGF-I, whereas birth weight, but not preeclampsia, was associated with IGFBP-1, after adjustment for gestational age.


CONCLUSIONS
Fetal growth restriction caused by severe or early preeclampsia is associated with lower umbilical levels of IGF-I than low birth weight caused by other conditions. Preeclampsia may contribute to the observed IGF-I reduction, either as part of the underlying causes of preeclampsia, or as a consequence of the disease.
Vatten
Lars J
LJ
Department of Community Medicine and General Practice, Norwegian University of Science and Technology, Trondheim, Norway. lars.vatten@medisin.ntnu.no
Ødegård
Rønnaug A
RA
Nilsen
Stein Tore
ST
Salvesen
Kjell A
KA
Austgulen
Rigmor
R
D000328:Adult; D015415:Biomarkers / Q000032:analysis; D001724:Birth Weight; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D006801:Humans; D007231:Infant, Newborn; D018970:Insulin-Like Growth Factor Binding Protein 1 / Q000097:blood*; D018972:Insulin-Like Growth Factor Binding Protein 3 / Q000097:blood*; D007334:Insulin-Like Growth Factor I / Q000032:analysis*; D011225:Pre-Eclampsia / Q000097:blood / Q000175:diagnosis*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D012016:Reference Values; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric
D015415:Biomarkers; D018970:Insulin-Like Growth Factor Binding Protein 1; D018972:Insulin-Like Growth Factor Binding Protein 3; D007334:Insulin-Like Growth Factor I