Inverse changes in fetal insulin-like growth factor (IGF)-1 and IGF binding protein-1 in association with higher birth weight in maternal diabetes

Clin Endocrinol (Oxf). 2007 Mar;66(3):322-8. doi: 10.1111/j.1365-2265.2006.02719.x.

Abstract

Objective: The insulin like growth factor (IGF) system plays a key role in regulating fetal growth, is metabolically regulated, and may influence development of increased birth weight in offspring of mothers with diabetes. We examined IGF-1 and IGF binding protein-1 (IGFBP-1) concentrations in cord blood samples from offspring of mothers with gestational and type 2 diabetes.

Design and patients: Case-control study of Maori and Pacific Island mothers recruited prospectively at Middlemore Hospital, South Auckland, New Zealand.

Measurements: Cord blood (for insulin, IGF-1 and IGFBP-1) was taken from umbilical vein at birth from singleton babies born after 32 weeks of gestation from138 mothers with gestational diabetes (GDM), 39 mothers with type 2 diabetes (T2DM) and 95 control mothers.

Results: Babies born to mothers with both GDM and T2DM had significantly increased birth weight (Z-score birth weight mean +/- SD: GDM 0.94 +/- 1.31, T2DM 0.53 +/- 1.1) compared to controls (Z-score birth weight -0.08 +/- 1.10). IGFBP-1 was significantly reduced in both diabetic groups (median interquartile range: GDM 67(31-137) ng/ml, T2DM 59(29-105) ng/ml, control 114(56-249) ng/ml). Cord IGF-1 was significantly increased in cord blood of infants of mothers with GDM (42.2 +/- 16.3 ng/ml vs. control 34.7 +/- 18.5 ng/ml) but not T2DM (38.7 +/- 17.4 ng/ml). In all offspring, IGF-1 and IGFBP-1 were positively and negatively correlated with birth weight, respectively.

Conclusions: Maternal diabetes results in inverse changes of circulating fetal IGF-1 and IGFBP-1 at birth. A decrease in circulating IGFBP-1 and to a lesser extent an increase in circulating IGF-1 may present an important mechanism that contributes to increased birth weight in diabetic pregnancies.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Birth Weight
  • Blood Glucose / analysis
  • Case-Control Studies
  • Chi-Square Distribution
  • Diabetes Mellitus, Type 2 / blood*
  • Diabetes, Gestational / blood*
  • Female
  • Fetal Blood / chemistry*
  • Fetal Macrosomia / blood
  • Humans
  • Infant, Newborn
  • Insulin / blood
  • Insulin-Like Growth Factor Binding Protein 1 / blood*
  • Insulin-Like Growth Factor I / analysis*
  • Linear Models
  • Postpartum Period / blood
  • Pregnancy
  • Pregnancy in Diabetics / blood*

Substances

  • Blood Glucose
  • Insulin
  • Insulin-Like Growth Factor Binding Protein 1
  • Insulin-Like Growth Factor I