A woman develops chickenpox at 39 weeks. She has a single fetus in the cephalic presentation. She has no other pregnancy complications.What is the best method to prevent neonatal infection?
**Core Concept**
The prevention of neonatal varicella infection in a pregnant woman with chickenpox is crucial to minimize the risk of congenital varicella syndrome and neonatal varicella. The Centers for Disease Control and Prevention (CDC) and other health organizations recommend a specific management approach for pregnant women who develop chickenpox close to term.
**Why the Correct Answer is Right**
Continuing the pregnancy for at least one week after the onset of chickenpox in the mother is the recommended approach. This is because the risk of congenital varicella syndrome decreases significantly if the fetus is exposed to the varicella-zoster virus (VZV) after 20 weeks of gestation. The exact mechanism is not fully understood, but it is believed that the fetal immune system is more mature and capable of responding to the virus after this gestational age. However, the risk of neonatal varicella infection remains, and the mother's immune system will provide some protection to the fetus during this period.
**Why Each Wrong Option is Incorrect**
**Option A is incorrect** because it implies that continuing the pregnancy indefinitely is the best approach. However, the risk of neonatal varicella infection increases with the duration of pregnancy, and other management options should be considered.
**Option B is incorrect** because the varicella zoster vaccine is not effective in preventing neonatal varicella infection in a baby born to a mother with chickenpox. Vaccination is generally recommended for non-immune pregnant women to prevent varicella infection.
**Option C is incorrect** because Varicella Zoster Immune Globulin (VZIG) is not effective in preventing neonatal varicella infection. VZIG may be used in specific situations, such as in a non-immune pregnant woman exposed to VZV, but it is not the recommended approach for a mother with chickenpox.
**Option D is incorrect** because inducing labor immediately after the onset of chickenpox in the mother increases the risk of neonatal varicella infection.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that the risk of congenital varicella syndrome is highest if the mother develops chickenpox before 20 weeks of gestation. In contrast, the risk of neonatal varicella infection is highest if the mother develops chickenpox close to term.
**✓ Correct Answer: A. Continue the pregnancy for at least one week.**