The triple marker screen test analyzes how likely an unborn baby is to have certain genetic disorders. It is also known as a multiple marker test. The exam measures the levels of three important substances in the placenta: alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG), and estriol.
Triple marker screening is administered as a blood test for women who are between 15 and 20 weeks pregnant. An alternative to this test is the quadruple marker screen test, which also looks at inhibin A.
A triple marker screen test takes a sample of blood and detects the levels of AFP, HCG, and estroil in it. Abnormal levels of these substances may indicate the presence of:
- Down syndrome
- Edwards syndrome
- neural tube defects (such as spina bifida and anencephaly).
- multiple infants
- an improper timeline (the pregnancy is further along or not as far along as once thought)
Triple marker screen tests help prospective parents prepare and assess options. They can also indicate multiple children.
Triple marker screen tests also alert doctors to watch a fetus more closely for other signs of complications.
There are no side effects for triple marker screen tests. Patients may experience slight discomfort due to the needle used to take blood, but that fades quickly.
The triple marker screen test is administrated in a hospital, clinic, doctor's office, or lab. The process is similar to any other blood test.
A doctor, nurse, or lab technician cleans the patch of skin where the needle will be inserted. A rubber band or other tightening device is placed on the arm to make a vein more accessible. The professional then inserts the needle to draw blood and removes it when the vial is full.
The site of injection is cleaned with a cotton swab or other absorbent material, and a bandage is placed on the wound.
The blood is then sent to a lab for assessment.
A triple marker screen test can indicate potential complications with a pregnancy, as well as the presence of multiple fetuses. This helps parents prepare for birth. If all the test results are normal, parents know that they are less likely to have a child with a genetic disorder.
There are no risks associated with taking the triple marker screen test.
Patients do not need to prepare for a triple marker screen test. There are no eating or drinking requirements beforehand.
The results of the triple marker screen test show the likelihood of an infant having a genetic disorder such as Down syndrome or spina bifida. Test results are not infallible. They merely show a probability.