ABSTRACT
A prenatal ultrasound performed at 20 weeks of gestation in a healthy multiparous woman identifies a large left multiloculated cervical mass, measuring 6 cm in greatest dimension, in a female fetus. The couple are given a grim prognosis by their obstetrician, but are referred to a maternal fetal medicine specialist for further evaluation. He repeats an ultrasound, confirming the diagnosis, as shown in Figure 1.1. The patient and her husband decide to continue the pregnancy and are referred to you for fetal consultation.
