Mirror syndrome associated with hydropic acardius in triplet pregnancy

Mirror syndrome is the association of triple edema, i.e. fetal, placental and maternal edema, with maternal preeclampsia. We here report the first case of mirror syndrome resulting from hydropic acardius in triplet pregnancy.

A 26-year-old nulliparous woman spontaneously conceived two living fetuses and one acardius, and suffered preterm rupture of the membranes at 23 2/7 weeks of gestation. We observed triple edema, hydropic acardius, placental edema, and maternal edema, together with maternal high blood pressure, proteinuria and low hematocrit, and therefore suspected the presence of mirror syndrome. Due to the prematurity of the fetuses, we closely observed her, awaiting fetal maturity. Three days later (23 5/7 weeks), cord prolapse occurred, leading to emergent cesarean section. Female infants, weighing 492 and 554 g, respectively, were born alive; the former died on the 13th postnatal day and the latter was healthy with no sequelae. An acardius weighing 860 g had vascular communication with the 492-gram fetus. Histological examination confirmed a monochorionic, triamniotic single placenta. The mother suffered from pulmonary edema and was treated in the intensive care unit under respiratory support, but soon improved.

When dealing with multifetal pregnancy, especially when complicated by an acardius, obstetricians must have the highest level of concern for the occurrence of mirror syndrome, a life-threatening condition both to the mother and the fetus.