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?

This is a contraindication for the Contraction Stress Test (CST) because it increases the risk of infection and umbilical cord prolapse.

A CST is a test that measures the baby’s heart rate during uterine contractions induced by oxytocin or nipple stimulation.

Choice A is wrong because gestational diabetes is not a contraindication for the CST.

It is a condition that affects how the body processes glucose during pregnancy and may cause complications such as macrosomia (large baby), hypoglycemia (low blood sugar) or preeclampsia (high blood pressure and protein in urine).

Choice B is wrong because mild preeclampsia is not a contraindication for the CST.

It is a condition that causes high blood pressure and protein in urine after 20 weeks of pregnancy and may affect the placenta, kidneys, liver or brain.

Choice C is wrong because preterm labor is a relative contraindication for the CST, not an absolute one.

It means that the test may be performed if the benefits outweigh the risks, but it should be avoided if possible because it may trigger early labor or delivery.

Preterm labor is defined as regular uterine contractions with cervical changes before 37 weeks of pregnancy.

Normal ranges for blood pressure are below 120/80 mmHg, for glucose are 70-100 mg/dL (fasting) or below 140 mg/dL (2 hours after eating), and for protein in urine are less than 300 mg/24 hours.

"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.