The aim of this study was to compare the fetal middle cerebral artery (MCA)
Doppler waveforms in growth-retarded twin fetuses with (n = 11) and withou
t (n = 24) twin-twin transfusion syndrome (TTTS). Umbilical artery (UA) and
fetal MCA Doppler velocity waveforms were recorded on admission, The mean
values of the UA pulsatility index (PI) of smaller twin fetuses with and wi
thout TTTS were significantly higher than those of normal singleton pregnan
cies, The mean values of the MCA PI of smaller twin fetuses in the TTTS gro
up (+0.7 +/- 1 SD) were significantly higher than those of normal singleton
pregnancies on admission, and these levels did not markedly change followi
ng amniocentesis, On the other hand, the values of the MCA of the growth-re
tarded fetuses without TTTS (-0.9 +/- 1 SD) were significantly lower than t
hose of normal singleton pregnancies, Our findings suggest that measurement
of fetal MCA PI is a useful method to assess growth-retarded fetuses in mo
nochorionic twin pregnancies, Copyright (C) 1999 S. Karger AG, Basel.