Donetsk Genetic Centre; Ukraine.

 Case report

A 34-year-old woman (G10P1) was referred to our centre for a routine first trimester screening at 12 weeks of her pregnancy. Our ultrasound examination revealed a singleton pregnancy (CRL = 54 mm) with several findings increasing suspicion of an abnormal chromosomal background:

• absent nasal bone;
• regurgitation at the level of the tricuspid valve;
• abnormal waveform of ductus venosus;
• abnormal structure of the fetal heart suspected of atrioventricular septal defect.

The nuchal translucency and frontomaxillary facial angle were normal (1.3 mm and 81° respectively). Biochemical screening revealed beta-hCG and PAPP-A of 0.921 and 0.186 MoM respectively. The combined risk of trisomy 21 was 1:2 and the diagnosis was confirmed by invasive testing.

Images 1, 2: 12 weeks of pregnancy (CRL 54 mm); the images show sagittal scans of the fetal head with absent nasal bone.

Images 3, 4: 12 weeks of pregnancy (CRL 54 mm); the image 3 represents a suboptimal sagittal scan of the fetal head and nuchal region, with normal nuchal translucency (1.3 mm). The image 4 shows sagittal scan of the fetal head with normal frontomaxillary facial angle (81°). 

Images 5, 6: 12 weeks of pregnancy (CRL 54 mm); the image 5 shows reversed flow at the level of the ductus venosus. The image 6 shows regurgitation at the level of the tricuspid valve of the heart.

Images 7, 8, 9, 10, 11, and 12: The images shows transverse color Doppler (Images 7-10) and gray scale (Images 11-12) scans of the fetal thorax at the level of the four chamber view of the heart. Atrioventricular septal defect was suspected. The images 8, 10, and 12 represent fusion of the images 7, 9, and 11 with a drawing elucidating the visible structures of the heart with atrioventricular septal defect.