CPT® Code 81511

Fetal congenital abnormalities, biochemical assays of four analytes (AFP, uE3, hCG [any form], DIA) utilizing maternal serum, algorithm reported as a risk score (may include additional results from previous biochemical testing)

The CPT® Code 81511 refers to a specific biochemical assay performed on maternal serum to assess the risk of fetal congenital abnormalities. This test measures four key analytes: alpha-fetoprotein (AFP), estriol (uE3), human chorionic gonadotropin (hCG) in any form, and Inhibin A Dimer (DIA). The results of this assay are reported as a risk score, which may also incorporate additional findings from prior biochemical tests. The primary purpose of this blood test is to evaluate the likelihood of certain chromosomal abnormalities in the fetus, including trisomy 18 and trisomy 21, which is commonly known as Down syndrome. Additionally, it helps in identifying the risk of open neural tube defects, such as spina bifida, as well as assessing potential pregnancy complications like preeclampsia and gestational trophoblastic disease. The test is most effective when conducted during a specific window of gestation, ideally between 14 weeks and 24 weeks and 6 days. The blood sample required for this analysis is obtained through a venipuncture, and the serum is subsequently analyzed using advanced techniques such as quantitative chemiluminescent immunoassay or electroluminescence assay.