Characteristics and management of mirror syndrome: a systematic review (1956-2016)

Objectives: To describe the clinical features of mirror syndrome and to correlate the effects of different treatments with the fetal outcomes. Data sources: Online search up to May 2016 was conducted in the PubMed, Embase (Ovid platform) and clinicalTrials. gov without restrictions of language, date or journal. Only papers providing both fetal and maternal presentations and outcomes were included. Results: The study included 74 papers (n = 111), with an additional two patients diagnosed at our center (n = 113). The mean gestational age at diagnosis was 27 weeks +/- 30 days (16-39 weeks). Whether early or late gestational age at diagnosis, and whether mother and fetus show symptoms simultaneously or on different dates, has insignificant impact on fetal outcome (P = 0.06 and P = 0.46, respectively). Edema (84%) followed by hypertension (60.1%) were the leading maternal findings. Fetal hydrops (94.7%) and placental edema (62.8%) were the commonest sonographic features. Procedures correcting fetal hydrops/anemia in utero as well as labor induction were the only treatment options correlated with improved fetal survival (chi(2) analysis, P = 0.01 and Fisher's exact test, P = 0.02; respectively). The overall rate of fetal/neonatal mortality was 67.26%. Conclusion: The gestational age at diagnosis and sequence of presentation have insignificant impact on fetal outcome. Improved fetal survival was associated with procedural interventions that correct fetal hydrops as well as labor induction.