While chickenpox is usually a mild and self-limiting disease, life-threatening complications can occur, particularly in risk groups such as pregnant women. In the case reported here, a 34-year-old woman, pregnant with her second child, was exposed to the varicella zoster virus (VZV) during the sixth week of pregnancy. Blood results showed seronegative status for VZV. Despite properly and well-timed administration of immunoglobulins, the patient developed chickenpox two weeks after exposure. Two days after developing symptoms she was admitted to the emergency room with fever and sudden shortness of breath. Radiological examination confirmed bilateral pneumonia, most probably due to VZV. Developing chickenpox during pregnancy is not only potentially dangerous for the unborn baby, but also for the mother. All medical specialists involved should be aware of the risks and consequences of this rare, yet dangerous, timing of chickenpox.