A client who is 15 weeks pregnant comes to the clinic for amniocentesis. Which finding can this test identify?

A client who is 15 weeks pregnant comes to the clinic for amniocentesis. Which finding can this test identify?

• A. Neural tube defects
• B. Chromosomal defects
• C. Sex of the fetus
• D. Placental location

Answer: (A)

Amniocentesis provides fetal cells and biochemical markers from the amniotic fluid, which allows screening for open neural tube defects. The standout finding for neural tube defects is an elevated alpha-fetoprotein level in the amniotic fluid, often accompanied by the presence of acetylcholinesterase, which together are highly specific for conditions like spina bifida or anencephaly. This test is routinely performed around mid-pregnancy because those markers become detectable in this window. While amniocentesis can also evaluate fetal chromosomes (karyotype) and ultrasound assesses placental location, the finding most directly identified by this test in this scenario is neural tube defects through the AFP (and acetylcholinesterase) profile.

Amniocentesis provides fetal cells and biochemical markers from the amniotic fluid, which allows screening for open neural tube defects. The standout finding for neural tube defects is an elevated alpha-fetoprotein level in the amniotic fluid, often accompanied by the presence of acetylcholinesterase, which together are highly specific for conditions like spina bifida or anencephaly. This test is routinely performed around mid-pregnancy because those markers become detectable in this window. While amniocentesis can also evaluate fetal chromosomes (karyotype) and ultrasound assesses placental location, the finding most directly identified by this test in this scenario is neural tube defects through the AFP (and acetylcholinesterase) profile.