A nurse is teaching a client who is at 15 weeks of gestation and is to undergo an amniocentesis. The nurse should explain that the purpose of this test is to identify which of the following conditions?
Explanation & Rationale
Choice A rationaleAmniocentesis detects anomalies in fetal chromosomes by analyzing amniotic fluid cells. It identifies genetic disorders like Down syndrome. Normal karyotype excludes major chromosomal abnormalities.Choice B rationaleRh incompatibility is identified by maternal blood tests, not amniocentesis. Blood type and antibody screening determine Rh status and risk of hemolytic disease in the fetus.Choice C rationaleCephalopelvic disproportion is assessed clinically and via ultrasound. It involves the pelvis and fetal head sizes, not amniocentesis.Choice D rationaleAmniocentesis can detect infections, but this is not its primary purpose. Polymerase chain reaction (PCR) identifies bacterial or viral DNA/RNA.Choice E rationaleAmniocentesis detects neural tube defects like spina bifida by measuring alpha-fetoprotein (AFP) levels in amniotic fluid. Elevated AFP suggests neural tube defects.