A nurse is providing education to a client who is scheduled to undergo chorionic villus sampling (CVS).

Which statement by the client indicates an understanding of this test?

"It is a screening test for spinal defects in the fetus."

The MSAFP test is a blood test that measures the amount of alpha-fetoprotein (AFP) in the mother’s blood.

AFP is a protein produced by the baby during pregnancy.The test helps to assess the baby’s risk of certain birth defects, such as neural tube defects, which are abnormalities in the development of the brain and spine.

A. “It is a diagnostic test for spinal defects in the fetus.” This statement is wrong because the MSAFP test is not a diagnostic test.

It only indicates the probability of having a spinal defect, but it does not confirm or rule out the condition.A diagnostic test, such as an ultrasound or amniocentesis, is needed to make a definitive diagnosis.

C. “It is a diagnostic test for chromosomal abnormalities in the fetus.” This statement is wrong because the MSAFP test is not a diagnostic test for chromosomal abnormalities either.

It only indicates the probability of having a chromosomal abnormality, such as Down syndrome, but it does not confirm or rule out the condition.A diagnostic test, such as a chorionic villus sampling (CVS) or amniocentesis, is needed to make a definitive diagnosis.

D. “It is a screening test for chromosomal abnormalities in the fetus.” This statement is partially correct, but not the best answer.

The MSAFP test alone is not very accurate for screening chromosomal abnormalities.It is usually combined with other blood tests and an ultrasound to form a more reliable screening test called a quad screen or an integrated screen.

The normal range of MSAFP levels varies depending on the gestational age of the baby and the laboratory methods used.Generally, the MSAFP levels increase until about 15 weeks of pregnancy and then decrease until delivery.The average MSAFP level at 15 weeks of pregnancy is about 38 ng/mL.However, different laboratories may have different reference ranges, so it is important to consult your healthcare provider for your specific results and interpretation.

This is because AFP levels vary according to the gestational age of the fetus, and reporting them as multiples of the median (MoM) allows for a standardized comparison.

Choice B is wrong because AFP results do not differentiate between neural tube defects and chromosomal abnormalities.

They only indicate an increased risk for these conditions, which need further testing to confirm.

Choice C is wrong because AFP results do not assess the risk of fetal demise or multiple gestation.

They only measure the amount of AFP in the maternal blood, which can be affected by various factors such as maternal weight, race, diabetes, and fetal anomalies.

Choice D is wrong because AFP results are reported as MoM regardless of factors such as maternal weight and race.

These factors are taken into account when calculating the MoM value, which adjusts for the expected variation in AFP levels among different populations.

Normal ranges for AFP MoM vary depending on the laboratory and the method used, but generally they are between 0.5 and 2.52.

Values above or below this range may indicate an increased risk for certain fetal conditions or complications.