ELEVATED 2ND-TRIMESTER AMNIOTIC-FLUID CONCENTRATION OF INSULIN-LIKE GROWTH-FACTOR BINDING PROTEIN-1 IN FETAL GROWTH-RETARDATION

OBJECTIVE: The aim was to study the levels of amniotic fluid and maternal serum insulin-like growth factor binding protein-1 levels at 15 to 16 weeks' gestation with regard to fetal growth in the third trimester. STUDY DESIGN: Amniotic fluid (n = 148) and maternal serum (n = 129) levels of insulin-like growth factor binding protein-1 were prospectively measured. RESULTS: Elevated amniotic fluid insulin-like growth factor binding protein-1 levels were related to fetal growth retardation. At a cutoff value of 3 multiples of the median a high-risk group comprising 16% of all pregnant women was identified. This group included 40% of all small-for-gestational age (birth weight < 10th percentile) and 55% of all very-small-for-gestational-age (birth weight < 5th percentile) infants. Maternal serum insulin-like growth factor binding protein-1 levels were not significantly elevated in these groups. CONCLUSION: In most cases of intrauterine growth retardation the disturbance may exist before the condition is detectable by ultrasonography. An elevated amniotic fluid insulin-like growth factor binding protein-1 level may be an early sign.