Findings:

Normal evaluation of fetal heart at 13 weeks antenatal scan on transvaginal colour doppler examination show, Four chamber heart, outflow tracts (RVOT, LVOT), inter-atrioventricular septum.

Discussion:

On colour doppler any signs of regurgitation, stenosis or valvular dysplasia can be ruled out. Any regurgitant flow on colour doppler will be seen as aliasing or mixing of colours.  Transvaginal ultrasound will provide better image resolution and good scan quality as compared to transabdominal ultrasound for early pregnancies.

Key-points:

Ductus venosus must be studied with fetal heart during NT scan.