Prenatal Test: Multiple Marker Test
en español: Examen prenatal: Cribado múltiple
Medically reviewed by: Armando Fuentes, MD
What Is the Multiple Marker Test?
The multiple marker test is a blood test offered to all pregnant women. Doctors use it to screen for chromosomal disorders and neural tube defects.
Test results can be combined with first trimester screening tests to give more accurate results (this is called an integrated screening test).
It is important to remember that this is a screening test, not a diagnostic test. If the test shows there might be a problem, another test must be done to confirm or rule out a diagnosis.
Why Is the Multiple Marker Test Done?
The multiple marker test is done between weeks 15 and 20 of a woman's pregnancy to screen for neural tube defects (such as spina bifida) and chromosomal disorders (such as Down syndrome and trisomy 18).
Depending on the number of things measured, the test also is called:
- a "triple screen" or "triple marker" because it looks at the levels of a protein, alpha-fetoprotein (AFP), and two pregnancy hormones, estriol and human chorionic gonadotropin (hCG)