## **Core Concept**
The rubella virus, also known as German measles, can cause congenital rubella syndrome (CRS) if a pregnant woman is infected, particularly during the first 20 weeks of gestation. The risk of CRS is highest if infection occurs during the first 12 weeks. Vaccination against rubella is crucial for preventing such congenital anomalies.

## **Why the Correct Answer is Right**
The best immediate course of action for a pregnant patient exposed to rubella virus, especially if she does not remember getting a rubella vaccination, is to check her immune status against rubella. This involves testing for rubella-specific IgG antibodies to determine if she has immunity. If she is not immune, the risk of congenital rubella syndrome (CRS) needs to be discussed, and termination of pregnancy might be considered if the infection occurred early in pregnancy. However, immediate action would focus on confirming her immune status.

## **Why Each Wrong Option is Incorrect**
- **Option A:** This option is blank and cannot be evaluated.
- **Option B:** This option is also blank and cannot be assessed.
- **Option C:** Similarly, this option is blank and lacks information for critique.
- **Option D:** This option is blank as well.

## **Clinical Pearl / High-Yield Fact**
A crucial point to remember is that rubella vaccination is typically given in combination with measles and mumps vaccines (MMR vaccine). Pregnant women are advised against receiving live vaccines like MMR, but checking for immunity is a critical step in managing potential exposures during pregnancy.

## **Correct Answer:** D. Check for rubella immunity.