Adropin concentrations in term pregnancies with normal, restricted and increased fetal growth.

OBJECTIVE

To determine levels of adropin (implicated in insulin resistance and endothelial dysfunction) in intrauterine growth restricted (IUGR), large (LGA) and appropriate for gestational age (AGA) pregnancies.

METHODS

Cord-blood (UC) adropin and insulin concentrations were measured in 30 IUGR, 30 LGA and 20 AGA full-term infants and their mothers (MS).

RESULTS

No significant differences in adropin concentrations were observed between the three groups. In the IUGR group MS adropin was significantly decreased when neonates had higher birth weights [b = -0.003, 95% CI -0.006 to 0.0, p = 0.043]. In all groups, MS adropin levels were positively correlated with UC ones (r = 0.282, p = 0.011) and were significantly increased in female neonates [b = 0.977, 95% CI 0.122-1.832, p = 0.026]. In the LGA group, MS insulin was negatively correlated with UC adropin (r =  -0.362 p = 0.049).

CONCLUSIONS

Increased maternal adropin levels in severe IUGR cases might represent a regulatory feedback mechanism against endothelial placental dysfunction. The positive correlation between maternal and umbilical cord adropin levels implies its transplacental transfer. Increased maternal adropin levels in female neonates could be attributed to interaction of adropin with fetal estrogens through vascular endothelial growth factor (VEGF). The negative correlation between maternal insulin and fetal adropin levels in the LGA group is probably attributed to their respective insulin resistance.