Mirror Syndrome: A Systematic Review of Fetal Associated Conditions, Maternal Presentation and Perinatal Outcome

INTRODUCTION: Mirror syndrome, also referred to as Ballantyne's syndrome, is normally defined as the development of maternal edema in association with fetal hydrops. The incidence of mirror syndrome is low and few cases have been published. We describe a case report in association with fetal Ebstein anomaly and provide a systematic review on the fetal associated conditions, maternal presentation and perinatal outcome reported for mirror syndrome. DATA SOURCES: A PubMed database search was done until December 2008 (English, French or German) without any restriction of publication date or journal, using the following key words: Ballantyne syndrome, Mirror syndrome, Triple edema, Pseudotoxemia, Maternal hydrops syndrome, Pregnancy toxemia, Acute second trimester gestosis, and Early onset preeclampsia. Reported cases were considered eligible when fetal associated conditions, maternal symptoms and fetal outcome were clearly described. RESULTS: Among 151 publications a total of 56 reported cases satisfying all inclusion criteria were identified. Mirror syndrome was associated with rhesus isoimmunization (29%), twin-twin transfusion syndrome (18%), viral infection (16%) and fetal malformations, fetal or placental tumors (37.5%). Gestational age at diagnosis ranged from 22.5 to 27.8 weeks of gestation. Maternal key signs were edema (80-100%), hypertension (57-78%) and proteinuria (20-56%). The overall rate of intrauterine death was 56%. Severe maternal complications including pulmonary edema occurred in 21.4%. Maternal symptoms disappeared 4.8-13.5 days after delivery. DISCUSSION: Mirror syndrome is associated with a substantial increase in fetal mortality and maternal morbidity.