Objectives

No abstract

The aim of this study was to determine the incidence of nuchal cord and its possible effect on nuchal translucency thickness at 10-14 weeks' gestation. Out of 316 consecutive pregnancies in which nuchal translucency thickness was measured transabdominally, 26 (8.23%) fetuses were shown to have the umbilical cord around the neck. The umbilical cord can be measured together with the nuchal translucency thickness when it passes around the fetal neck and this adds a mean of 0.8 mm to the actual translucency measurement. After the thickness of the cord was subtracted, the measurements of nuchal translucency thickness did not differ from those in the overall population studied. Of the 22 fetuses available for follow-up, a nuchal cord was found in only one at 20 weeks and in none at delivery. Our findings indicate that the presence of a nuchal cord may bias the results of fetal nuchal translucency measurement and that the use of color Doppler might decrease the false-positive rate in screening for fetal aneuploidy by nuchal translucency measurement at 10-14 weeks' gestation.

The venous circulation of the fetal brain can be identified by color Doppler. The gestational age-related decrease in resistance and increase in flow velocities suggest that hemodynamic studies of the cerebral transverse sinus might have clinical implications in studying compromised fetuses.