Mirror syndrome in a Chinese hospital: diverse causes and maternal fetal features

Objective: To investigate the clinical characteristics of mirror syndrome. Methods: Retrospective analysis of cases with mirror syndrome. Data of clinical manifestations, laboratory examinations, placental morphology, treatment and prognosis of these patients were obtained and studied. Results: Five cases satisfying the inclusion criteria for mirror syndrome were identified from our hospital database. The incidence of the condition was 0.0154% in China. Mirror syndrome was associated with Rhesus isoimmunization, intrauterine parvovirus B19 infection, fetal neuroblastoma, fetal heart malformation and unknown cause respectively. Fetal symptoms were multi-hydrocele and fetal heart failure complicating fetal hydrops. All of the cases manifested maternal hydrops and hemodilution, the other most common symptoms included hypertension, proteinuria, hypoalbuminemia, anemia, thrombocytopenia and elevated uric acid levels. Fetal outcomes in this study were poor with a perinatal mortality rate of 100%. Placentomegaly was observed in most cases and placental morphology showed villous edema, increased intervillous fibrin deposition and one rare case of fetal adrenal neuroblastoma. Resolution of maternal symptoms was noted within 3–30 days after delivery. Conclusion: Mirror syndrome is associated with a substantially increased risk of fetal death and severe maternal complications. Early diagnosis of this condition during pregnancy is crucial for providing proper treatments and achieving better clinical outcomes.