There is evidence that Doppler US of
blood flow in the umbilical arteries improves management
and outcome in high-risk pregnancies w67x. Although the routine
use of Doppler US in low-risk pregnancies is not recommended,
it is of established value in the evaluation of fetal
well-being in cases of IUGR. Doppler US in fetal vessels
(arterial and venous) assesses fetal adaptation to chronic
hypoxemia. There is no evidence that fetal Doppler investigation
is of value in timing delivery for the management of
PT pregnancies.
There is no agreement on the optimal monitoring techniques
or the interval at which these tests should be applied.
The most commonly reported frequency is to do a test twice
a week even without evidence that these tests improve outcome
of PT pregnancy. US assessment of fetal size should
not be performed at intervals -2 weeks. Assessment of fetal
growth/size would appear to be critical to successful identification
of high fetal/neonatal risk in PT pregnancies.