A client asks the nurse about the risks and complications associated with prenatal ultrasound.

Which of the following responses by the nurse is accurate?

"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 finding indicates that the umbilical cord is being compressed, which can reduce the blood flow and oxygen supply to the fetus.

Variable decelerations are abrupt decreases in the fetal heart rate (FHR) that vary in shape, duration, and degree of fall below the baseline.

They are seen as W- or U-shaped waves on the monitor.

Choice B is wrong because fetal hypoxia is not indicated by variable decelerations, but by late decelerations, which are gradual decreases in the FHR that begin after the peak of the contraction and return to baseline after the contraction ends.

Late decelerations are associated with uteroplacental insufficiency, which means that the placenta is not delivering enough oxygen to the fetus.

Choice C is wrong because normal placental function is not indicated by variable decelerations, but by reassuring FHR patterns, such as moderate variability (6 to 25 beats per minute) and accelerations (increases in the FHR above the baseline).

Normal placental function ensures adequate fetal oxygenation and well-being.

Choice D is wrong because adequate fetal oxygenation is not indicated by variable decelerations, but by reassuring FHR patterns, such as moderate variability and accelerations.

Adequate fetal oxygenation means that the fetus is not experiencing hypoxia or distress.

Normal ranges for FHR are 110 to 160 beats per minute at term and 120 to 160 beats per minute before term.

Normal ranges for uterine contractions are 2 to 5 contractions in 10 minutes, lasting less than 90 seconds each.