Procedure
   Ultrasound specifically looking for features of Down syndrome or other chromosome abnormalities. These findings could include shorted humerus and/or femur bones, pylectasis, echogenic foci in the heart or bowel, other major birth defects (such as a heart defect).

Timing
   18-20 weeks gestation*

Detection Rate

• up to 80% detection of Down syndrome
• greater than 90% detection of trisomies 13 and 18
• greatr than 95% detection of open neural tube detects

Miscarriage Risk
   NONE

*Technically this screening can be performed from 14-20 weeks gestation.  Even though an assessment for Down syndrome can be provided earlier in pregnancy, evaluations prior to 18 weeks gestation may provide suboptimal images of the fetal anatomy such as heart and spine.  Therefore we highly recommend and prefer patients be referred between the range of 18-20 weeks gestation for optimal views providing a risk assessment for Down syndrome, trisomy 13, trisomy 18, open neural tube defects, and other structural abnormalities.