Cord blood cortisol level is lower in growth-restricted newborns.
OBJECTIVE
To establish the difference in plasma cortisol concentrations between newborns with intrauterine growth-restricted (IUGR) and appropriate for gestational age (AGA) birthweights.


METHODS
We measured plasma cortisol concentrations in the umbilical venous cord blood of 68 IUGR newborns and 71 AGA birthweight newborns. All newborns were delivered in term, vaginally, in the morning, within 8 hours and had APGAR scores greater or equal to eight.


RESULTS
There was no significant difference between compared groups according to maternal age, parity, gestational age and neonatal gender. Neonatal plasma cortisol levels were significantly lower in the IUGR (median: 312.3 mmol/L, min-max: 158.9-588.1 mmol/L) compared to the AGA group (median: 458.7 mmol/L, min-max: 314.5-718.5 mmol/L) (Mann-Whitney U-test; P<0000). The probability of having a cortisol plasma level greater than or equal to 458.7 mmol/L for IUGR newborns was only 1:12, and to have cortisol plasma level less than or equal to 312.3 mmol/L for AGA newborns was much lower (0:34). In the range of plasma cortisol level between 312.3 mmol/L and 458.7 mmol/L, no statistically significant difference in the plasma cortisol level between IUGR and AGA newborns was found.


CONCLUSIONS
Neonatal plasma cortisol level is lower in the IUGR compared to the AGA group. Our results suggest that endocrine relationships seem to be lost in a specific group of the IUGR newborns. Although we usually tend to simplify the problem and declare only one cause, this time it is impossible. It is probable that the cause is hidden in small and insufficient placenta with deranged auto-regulation of placental 11beta-HSD-2 mechanism.
Strinic
Tomislav
T
Department of Obstetrics and Gynecology, Clinical Hospital Split, Split, Croatia.
Roje
Damir
D
Marusic
Jelena
J
Capkun
Vesna
V
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2 / Q000032:analysis; D005260:Female; D005312:Fetal Blood / Q000737:chemistry*; D005317:Fetal Growth Retardation / Q000097:blood* / Q000503:physiopathology; D005333:Fetus / Q000503:physiopathology; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007231:Infant, Newborn; D008297:Male; D010920:Placenta / Q000737:chemistry / Q000503:physiopathology
D043209:11-beta-Hydroxysteroid Dehydrogenase Type 2; C468387:HSD11B2 protein, human; D006854:Hydrocortisone