A client who is 15 weeks pregnant comes to the clinic for amniocentesis. Which finding would indicate neural tube defects?

A client who is 15 weeks pregnant comes to the clinic for amniocentesis. Which finding would indicate neural tube defects?

• A. Gestational age
• B. Paternal age
• C. Maternal anemia
• D. Neural tube defects

Answer: (D)

Neural tube defects are detected by specific markers in amniotic fluid, because open defects allow fetal proteins like alpha-fetoprotein (AFP) to leak into the fluid and acetylcholinesterase to be present. The most informative finding is elevated amniotic fluid AFP, often with the presence of acetylcholinesterase, which together strongly indicate an open neural tube defect. Gestational age, paternal age, and maternal anemia do not specifically signal neural tube defects. The option describing neural tube defects aligns with the diagnosis itself—if this finding is present, it indicates the condition. In practice, elevated AFP from maternal screening prompts amniocentesis to assess AFP and acetylcholinesterase for confirmation.

Neural tube defects are detected by specific markers in amniotic fluid, because open defects allow fetal proteins like alpha-fetoprotein (AFP) to leak into the fluid and acetylcholinesterase to be present. The most informative finding is elevated amniotic fluid AFP, often with the presence of acetylcholinesterase, which together strongly indicate an open neural tube defect. Gestational age, paternal age, and maternal anemia do not specifically signal neural tube defects. The option describing neural tube defects aligns with the diagnosis itself—if this finding is present, it indicates the condition. In practice, elevated AFP from maternal screening prompts amniocentesis to assess AFP and acetylcholinesterase for confirmation.