mrcem2-1334

A 3 year old is brought to the emergency department due to concern that the patient has developed a fever, symptoms of a cold, and a widespread rash with blisters. You diagnose the child with chickenpox and advise the mother on how to manage the condition. The mother informs you that she is 12 weeks pregnant and is worried about the potential consequences of contracting chickenpox during pregnancy.

What is the most significant complication of chickenpox infection for the mother during pregnancy?