Ductus venosus assessment at the time of nuchal translucency measurement in the detection of fetal aneuploidy.

OBJECTIVE

To assess the potential value of ductus venosus Doppler studies in the detection of fetal aneuploidy on measurement of nuchal translucency.

METHODS

The pulsatility index for veins (PIV) and the lowest velocity during atrial contraction (A-wave) were determined in the fetal ductus venosus in 3382 consecutive pregnancies at 10 to 14 weeks and studied from December 1996 to December 2001. Nuchal translucency was also measured. The population studied included 1664 pregnancies at high risk and 1718 at low risk for fetal aneuploidy.

RESULTS

In relation to the prenatal detection of trisomy 21, the ductus venosus PIV was increased in 75% (36/48), the A-wave was decreased in 58% (28/48), and nuchal translucency was enlarged in 81% (39/48) of the trisomy 21 fetuses [71% (22/31) when nuchal translucency referrals were excluded]. The corresponding figures for trisomies 18 and 13 were 71, 58 and 83%, respectively, being 33, 33 and 33% for other unbalanced anomalies.

CONCLUSION

There is a high proportion of fetuses with trisomies 21, 18 and 13 (around 75%) in which the ductus venosus PIV is increased (above the 95th percentile) at 10 to 14 weeks, this proportion being similar to that observed for increased nuchal translucency measurement.