Prenatal Laboratory Services

First Trimester Risk Assessment also known as the Combined Test includes two biochemical markers (PAPP-A and total HCG) performed in the Prenatal Laboratory, and a nucal translucency measurement which is performed by a certified sonographer in the obstetric clinic. This test is performed between 11 and 13 weeks of pregnancy and detects 83% of Down syndrome pregnancies. A second trimester alpha-fetoprotein (AFP) test is available to detect neural tube defects. The First Trimester Risk Assessment is available to patients in a special instant read format at the Yale Maternal Fetal Medicine Clinic.

Quad screen is a second trimester Down syndrome risk assessment which includes four biochemical markers, AFP, total HCG, estriol and Inhibin A. The test is performed between 15 and 18 weeks of pregnancy (but between 14 and 22 weeks is possible). The Quad screen detects 80% of Down syndrome pregnancies and includes screening for neural tube defects.

Integrated screen combines the First Trimester Risk Assessment with the second trimester Quad Screen. This test currently is the most effective Down syndrome screen available detecting 93% of Down syndrome pregnancies. The test also includes screening for neural tube defects.

Biochemical Screen combines PAPP-A drawn between 11 and 13 weeks of pregnancy in the first trimester with the Quad screen drawn between 15 and 18 weeks of the second trimester of pregnancy. This test is available in the event that a nucal translucency measurement can not be obtained and is the second most effective Down syndrome screen with a detection rate of 86- 88% of Down syndrome pregnancies. The test also includes screening for neural tube defects. 

Cystic Fibrosis newborn screening
The Prenatal Laboratory and Molecular Diagnostics Laboratory provide a comprehensive Cystic Fibrosis neonate screening service to Fairfield, New Haven, Middlesex and New London counties. The Prenatal Laboratory performs immunoreactive trypsinogen (IRT) test on filter paper blood specimens, which is followed by genetic tests for the most common mutations. The genetic testes are performed in the Molecular Diagnostics laboratory. The Cystic Fibrosis Center at Yale New Haven Hospital follows up with each newborn identified with Cystic Fibrosis. Our goal is to identify an affected newborn and enroll them in a Cystic Fibrosis support/treatment program within one week of receipt of the filter paper specimen.