Trisomy 21

• Nuchal Translucency: >3.5 mm in 1st trimester
• Maternal Serum: decreased AFP and estriol, increased HCG and Inhibin A
• Echogenic bowel
• Short humerus and femur
• Hydrops fetalis
• Cystic hygroma
• Atrioventricular septal defect
• Duodenal atresia
• Intracardiac echogenic focus (IEF) - calcification in papillary muscle, can be normal
• Renal pelviectasis
• Hypoplastic nasal bone

Nuchal thickening	Short Humerus	Cystic Hygroma
Atrioventricular septal defect	Intracardiac echogenic focus	Hypoplastic nasal bone