Tests & Services for Prenatal Diagnosis & Genetics at University of Colorado Hospital

First and Second Trimester Sequential Screening

This screening combines an ultrasound performed between 10.5 and 14 weeks of pregnancy, with a first or a first and second trimester blood test.

The screening determines risk to the fetus for:

• Down syndrome
• Extra chromosomal material (Trisomy 18)
• Open neural tube defects (failure of the bones and tissue over the spine to close)

The American College of Obstetrics and Gynecology now recommends First Trimester Screening for all pregnant women.

Genetic Sonogram

The genetic sonogram is an ultrasound exam that looks for physical signs that may indicate chromosome abnormalities in the fetus. The sonogram also helps to determine organ development in the fetus.

Fetal Echocardiography

The fetal echocardiography is an ultrasound exam that looks for abnormalities in the heart of the fetus. It is recommended for patients with:

• Family history of congenital heart disease
• Exposure to certain medications
• Specific maternal conditions such as diabetes or lupus

It is also recommended in fetuses with:

• Known chromosomal abnormalities
• Other non-heart abnormalities

Chorionic Villus Sampling (CVS)

In CVS testing, a small amount of tissue from the placenta is removed to analyze the chromosomes of the fetus.  CVS is performed between 10.5 and 12.5 weeks of pregnancy.

Amniocentesis

A small amount of amniotic fluid (the fluid which surrounds the fetus) is removed and analyzed to test the chromosomes of the fetus. 

For example, amniocentesis is used to assess the risk for a neural tube defect.  Amniocentesis is most commonly performed between 16 and 18 weeks of pregnancy.