Which of the following findings is normal for the fetal umbilical cord?

• A. Three vessels: two arteries and one vein.
• B. Two vessels: one artery and one vein.
• C. Two vessels: two arteries and no veins.
• D. Three vessels: two veins and one artery.

Answer: (A)

Normal fetal circulation in the umbilical cord has three vessels: two arteries and one vein. The arteries carry deoxygenated blood from the fetus to the placenta, while the vein returns oxygenated blood back to the fetus. This classic three-vessel setup supports proper exchange of oxygen and nutrients.

Among the options, the arrangement of three vessels with two arteries and one vein is the standard, making it the best answer. A two-vessel cord (one artery and one vein) is a known variation that can be associated with other fetal issues, but it is not the typical normal finding. A cord with two arteries and no vein would lack a pathway for returning blood to the fetus, which is not normal. A cord with two veins and one artery is also not the usual anatomy and is not considered normal.