ALPHA FETO PROTEIN(AFP), MATERNAL SERUM

Alpha-Fetoprotein (AFP), Maternal Serum

What it is

The Alpha-Fetoprotein (AFP), Maternal Serum test measures the level of AFP, a protein produced by the fetal liver, in the mother’s blood during pregnancy. It is typically performed between the 15th and 20th week of pregnancy as part of the second-trimester maternal serum screening (triple or quad screen). Abnormal AFP levels may signal certain fetal conditions or pregnancy-related issues.

Uses

This test is used to screen for neural tube defects (such as spina bifida and anencephaly), abdominal wall defects, and chromosomal abnormalities including Down syndrome when combined with other markers. It can also help detect multiple pregnancies or assess overall fetal and placental health.

Symptoms That May Lead to the Test

Unlike other lab tests, the AFP maternal serum test is a routine prenatal screening and does not require specific symptoms. However, it is especially important for women with risk factors such as a family history of birth defects, diabetes, or advanced maternal age.

Abnormal Results

High AFP Levels: May indicate neural tube defects, abdominal wall defects, multiple pregnancies, or inaccurate pregnancy dating. Rarely, they may be linked to fetal demise or other complications.

Low AFP Levels: May suggest chromosomal abnormalities such as Down syndrome (trisomy 21) or Edwards syndrome (trisomy 18), or may reflect incorrect gestational age estimation.

Abnormal results do not confirm a diagnosis but indicate the need for further testing, such as ultrasound or amniocentesis.

Risks

The test requires only a routine blood draw, which carries minimal risks like slight pain, bruising, or dizziness. There are no direct risks to the baby.