A pregnant woman at 16 weeks with bipolar I disorder is stable on lithium. She wants to know about risks. Which SPECIFIC fetal cardiac anomaly is associated with first-trimester lithium exposure?

• A Transposition of great arteries
• B Tetralogy of Fallot
• C Ebstein's anomaly (tricuspid valve malformation) ✓
• D Ventricular septal defect

Explanation

First-trimester lithium exposure is associated with Ebstein's anomaly — a congenital malformation of the tricuspid valve with downward displacement into the right ventricle. The absolute risk is small (estimated 1-2 per 1000 exposed, compared to 1 per 20,000 in the general population), but it must be discussed. The risk-benefit analysis must weigh fetal risk against maternal relapse risk (which is high if lithium is discontinued). Fetal echocardiography at 18-20 weeks is recommended.

Reference: Kaplan & Sadock's Synopsis of Psychiatry, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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