Maternal serum hepcidin is low at term and independent of cord blood iron status

Hepcidin is the key regulator of iron homeostasis. The aims of this study were to determine serum hepcidin concentrations and reference ranges in pregnant women and cord blood of newborns at term and to evaluate the associations between hepcidin concentrations and iron status parameters.

A total of 191 pregnant women-newborn pairs were studied in Kuopio University Hospital, Finland. The measured parameters were serum hepcidin, ferritin, transferrin receptor, transferrin saturation, red cell indices, and erythropoietin.

The hepcidin concentration in pregnant women was significantly lower than in cord blood at term [geometric mean concentration (GMC) (95% confidence intervals) in pregnant women 10.7 ng/mL (8.5-13.4 ng/mL) vs. GMC of cord blood hepcidin 69.3 ng/mL (55.3-86.8 ng/mL), P<0.001, adjusted analysis of variance]. Hepcidin was undetectable in 12% of mothers. Hepcidin concentration in pregnant women was the lowest in those who had the lowest iron status. However, maternal hepcidin concentration was not associated with cord blood hepcidin or iron status markers. Hepcidin concentration in cord blood was associated with cord blood iron status, but not with maternal iron status.

At term pregnancy, hepcidin concentrations are very low, allowing maximal availability of iron for the fetus. Maternal and cord blood hepcidin levels were independently associated with either maternal or cord blood iron status.