Why Not Lower the Cutoff on Maternal Serum α-Fetoprotein Screens

question 5

Multiple Choice

Why not lower the cutoff on maternal serum α-fetoprotein screens so that near complete ascertainment of neural tube defects via the screen would be had?

• A) It would be too expensive
• B) There would be too many false positives
• C) It would decrease the sensitivity for Down syndrome detection
• D) MSAFP levels that low cannot be measured
• E) It would no longer be possible to discriminate between the common trisomies via maternal serum screening

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Definitions:

Enzymes

Proteins that catalyze, or speed up, chemical reactions within living organisms without being consumed in the process.

Refractory Period

Time following an action potential when a neuron is unable to conduct another nerve impulse.

Ejaculation

The discharge of semen from the male reproductive tract as a result of sexual climax.

Spermatogenesis

The biological process of sperm cell development in males, which takes place in the testes and involves the production and maturation of spermatozoa.