Nuchal translucency thickness and fetal cardiac flow velocity in normal fetuses at 11-13 weeks of gestation

Abstract

Objective: To investigate the relationship between nuchal translucency thickness and cardiac flow velocity in normal fetuses at 11-13 weeks of gestation.

Subjects and methods: Eighteen normal pregnancies were prospectively studied with transvaginal sonography and pulsed and color Doppler ultrasound. Flow velocities at the fetal atrioventricular valves (mitral and tricuspid valve) and outflow tract levels (ascending aorta and pulmonary artery), and at the descending aorta were recorded. Nuchal translucency thickness was also measured.

Results: Mitral peak velocity during early diastolic filling correlated with gestational age. Mitral peak velocities during early diastolic filling and atrial contraction, tricuspid peak velocity during early diastolic filling, ascending aorta peak velocity, and pulmonary artery peak velocity correlated well with nuchal translucency thickness. There was an inverse correlation between umbilical artery pulsatility index and gestational age.

Conclusions: These results suggest that the increase of nuchal translucency thickness in normal fetuses at 11-13 weeks of gestation may be the consequence of changes in fetal cardiac functions.