Maternity Nursing: Antepartum Q 29
A 26-year old multigravida is 14 weeks pregnant and is scheduled for an alpha-fetoprotein test. She asks the nurse, “What does the alpha-fetoprotein test indicate?” The nurse bases a response on the knowledge that this test can detect:
A. Kidney defects
B. Cardiac defects
C. Neural tube defects
D. Urinary tract defects
Correct Answer: C. Neural tube defects.
The alpha-fetoprotein test detects neural tube defects and Down syndrome. Alpha-fetoprotein (AFP) is a plasma protein produced by the embryonic yolk sac and the fetal liver. AFP levels in serum, amniotic fluid, and urine functions as a screening test for congenital disabilities, chromosomal abnormalities, as well as some other adult occurring tumors and pathologies.
Option A: In some cases, one or both kidneys may fail to develop. In other instances, an abnormality may be present that blocks the outflow of urine. This blockage may cause urine to back up into the kidney, a condition called hydronephrosis, which causes the kidney to appear enlarged on the ultrasound test. Another common abnormality is called reflux. This occurs when a valve-like mechanism at the point where the ureter joins the bladder does not work, allowing urine to wash back up into the kidney.
Option B: The baby’s heart begins to form immediately after conception and is complete by eight week’s gestation. The heart begins as a tube-shaped structure that twists and divides to form the heart and heart valves. A congenital heart defect usually occurs because the heart does not twist or divide normally. Some mothers wonder if drugs, alcohol, or medications contributed to their child’s heart defect. In most cases, we don’t know why these defects occur. Although, some heart defects can run in families or be related to a disease the mother has, diabetes mellitus, for example.
Option D: Common birth defects of the urinary system include hypospadias, obstructive defects of the renal pelvis, and renal agenesis. Hypospadias is characterized by the location of the urethral opening on the underside of the penis. Obstructive defects of the renal pelvis prevent urine from entering the bladder.