Circulating follistatin in the human foetus at term birth.

BACKGROUND

Prenatal weight partitioning is gender specific, and infants born small for gestational age (SGA) have a lower fat mass and a lower fat-free mass than infants born appropriate for gestational age (AGA). Follistatin is an adipokine with adipogenic properties.

OBJECTIVES

We examined whether follistatin circulates in the human foetus at term birth and, if so, whether cord blood follistatin relates to birthweight and neonatal body composition.

METHODS

The study population was comprised of 248 term newborns (128 girls, 120 boys; 133 AGA, 115 SGA). The main outcome measures used for the study were birthweight, follistatin and insulin in umbilical cord serum, and neonatal body composition by absorptiometry.

RESULTS

Follistatin was detectable in all cord serum samples. Cord follistatin concentrations were similar in girls and boys, being about 25% higher (P < 0.001) in SGA than AGA infants. In SGA infants, higher follistatin concentrations related to lower fat mass.

CONCLUSION

[corrected] Follistatin is detectable in the circulation of the human foetus at term birth. The circulating levels of follistatin, an adipogenic adipokine, are higher in SGA than AGA infants, particularly so in SGA infants with a lower fat mass.