Adnexal masses in the neonate, child, and adolescent

The etiology of a fetal or neonatal ovarian cyst almost universally is a functional cyst. 1-3 Only rarely will pathology such as a mature teratoma, 1,2,4 granulosa cell tumor or cystadenoma 5 be present. Management of the antenatal or neonatal ovarian cyst requires consideration of ovarian preservation and avoidance of complications, in particular ovarian torsion, a challenging diagnosis in infancy.