Lithium is used in a pregnant woman. Which of the following congenital anomaly occurs in foetus –
**Core Concept**
Lithium is a medication used to treat bipolar disorder, and when used during pregnancy, it can have teratogenic effects on the developing fetus. The underlying concern is the potential for lithium to cause cardiac malformations due to its effects on cardiac development.
**Why the Correct Answer is Right**
Lithium can interfere with the normal development of the heart, particularly the outflow tract, leading to an increased risk of congenital heart defects. This is thought to occur due to lithium's inhibition of the sodium-potassium ATPase pump, which can disrupt the normal functioning of the cardiac cells. As a result, the developing heart may not form properly, leading to an increased risk of cardiac malformations.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because lithium is not primarily associated with an increased risk of neural tube defects.
* **Option B:** This option is incorrect because while lithium can have effects on the developing fetus, it is not primarily associated with an increased risk of limb abnormalities.
* **Option C:** This option is incorrect because lithium is not primarily associated with an increased risk of renal abnormalities.
**Clinical Pearl / High-Yield Fact**
It's essential for clinicians to be aware of the potential risks of lithium during pregnancy, particularly the increased risk of cardiac malformations. Regular monitoring of fetal heart rate and ultrasound examination can help identify any potential issues early on.
**Correct Answer:** C. Ebstein's anomaly.