Protein S100β in Late-Pregnancy Fetuses with Low Birth Weight and Abnormal Cerebroplacental Ratio.

OBJECTIVE

To evaluate the umbilical cord venous S100β levels in late-pregnancy fetuses with abnormal growth and cerebral redistribution.

METHODS

The pulsatility index of the umbilical and middle cerebral arteries and the cerebroplacental ratio (CPR) were measured in 132 fetuses at ≥34 weeks, and the CPR was converted into multiples of the median (MoM). A blood sample from the umbilical vein was collected at birth, and the umbilical venous S100β levels were evaluated in small and non-small for gestational age (SGA) fetuses, with and without abnormal Doppler indices. The levels of S100β were correlated with birth weight (BW) centile, CPR MoM and cord venous pH.

RESULTS

While CPR MoM correlated with BW centile, S100β showed no correlation with any of the studied fetal parameters. In addition, no differences were observed in S100β level according to BW centile or Doppler parameters, neither was there any difference between SGA with low CPR MoM and non-SGA with normal CPR MoM.

CONCLUSION

Late-pregnancy fetuses with abnormal growth or cerebral redistribution have normal cord blood levels of S100β at birth. In these fetuses, the potential consequences of chronic hypoxemia on the fetal brain might not be detectable using tissue necrosis markers.