Am J Perinatol 1998; 15(1): 23-28
DOI: 10.1055/s-2007-993893

© 1998 by Thieme Medical Publishers, Inc.

Insulin-Like Growth Factors, Their Binding Proteins, and Fetal Macrosomia in Offspring of Nondiabetic Pregnant Women

Arnon Wiznitzer1 , E. Albert Reece2 , Carol Homko2 , Boris Furman1 , Moshe Mazor1 , Joseph Levy2
  • 1Department of Obstetrics and Gynecology, Soroka Medical Center, Clinical Laboratory of Endocrinology, Ben-Gurion University, Beer-Sheva, Israel
  • 2Department of Obstetrics, Gynecology and Reproductive Sciences, Temple University School of Medicine, Philadelphia, Pennsylvania
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Publication History

Publication Date:
04 March 2008 (online)


The Objective of this paper is to determine the relation between fetal macrosomia in offspring of nondiabetic women, and the levels of insulin-like growth factors (IGF-I, IGF-II), insulin growth factor binding protein-3 (IGFBP-3) and insulin, in maternal and neonatal compartments. Serum samples were obtained from normal pregnant women (n = 60) and their neonates (n = 60) between 37-41 weeks' gestation (mean 39 ± 9). Neonates were categorized as appropriate for gestational age (AGA; 10th-90th percentile; n = 20), and large for gestational age (LGA; >90th percentile; n = 40). Maternal and neonatal serum samples were analyzed for levels of IGF-I, IGF-II, IGFBP-3 and insulin, by specific radioimmunoassays (RIAs). Serum levels were correlated with birth weight. The mean birth weight of the AGA group was 3296 ± 500 g versus 4201 ± 300 g for the LGA group (p <0.0001). Cord blood IGF-I was statistically higher in LGA group than in the AGA infants, (139 ± 67 ng/mL and 80 ± 32 ng/mL, respectively; p <0.0001). There was no correlation between maternal IGF-I serum levels and birth weight (363 ± 131 in the AGA vs. 308 ± 158 in the LGA group). IGF-II in maternal and cord blood did not correlate with fetal weight. Cord blood IGFBP-3 was significantly higher in the LGA group (1.1 ± 0.07 μg/mL) than in the AGA group (0.96 ± 0.05 μg/mL; p <0.05). Maternal insulin levels were similar between the two groups. Neonatal insulin levels were higher in the LGA group (18 ± μU/mL) as compared to the AGA group (16 ± μU/mL), however, this difference did not reach statistical significance. Fetal cord blood levels of IGF-I and IGFBP-3 are directly correlated with the birth weight of large for gestational age fetuses. These data suggest that the somatotropic axis plays a role in fetal growth. Additionally, insulin growth factor-1 appears to be an in utero growth promoter in the development of fetal macrosomia in infants of nondiabetic women.