Question

Most common congenital anomaly associated with lithium:

• A. Cardiac malformations
• B. Neural tube defects
• C. Renal anomaly
• D. Fetal hydantoin syndrome

Hint:

Think Ebstein anomaly of the tricuspid valve.

Answer 1

The Correct Option is A

Lithium is a mood stabiliser with a single famous fetal hazard, and matching it to the right organ system solves the question.

When lithium is used early in pregnancy, the heart is the target. The textbook lesion is Ebstein anomaly, where the tricuspid valve sits too low and the right ventricle is partly atrialised. Because this is a structural defect of the heart, the umbrella answer is congenital cardiac malformation.

The other choices belong to different drugs. Spinal and cranial neural tube defects point to valproate and carbamazepine. Fetal hydantoin syndrome is the signature of phenytoin. A primary fetal renal malformation is not the recognised lithium effect.

So the heart, specifically the tricuspid valve, is the answer.
\[\boxed{\text{Cardiac malformations}}\]