Chorioangiomas are benign placenta tumors histologically corresponding either to hamartomas derived from primitive chorionic mesenchyma or placental hemangiomas arising from chorionic plate [1]. Large or giant chorioangiomas, defined as measuring more than 4–5 cm in diameter, have an estimated prevalence varying from one in 9000 to one in 50 000 pregnancies [1], and have been associated with a number of fetal complications including anemia, polyhydramnios, hyperdynamic circulation and cardiomegaly, hydrops, and growth restriction [2–6]. In view of these complications and the associated high perinatal death rate (30–40%), a number of therapeutic interventions have been attempted with limited success in most cases [5, 7, 8].

Here we report a case of giant chorioangioma, fetal hydrops, additionally complicated by severe anemia, mild cardiomegaly with hyperdinamic heart circulation and maternal mirror syndrome.

Around 50% of large chorioangiomas cases develop fetal and maternal complications that required either elective delivery or intervention for tumor-related effects [9].

Mirror syndrome (Ballantyne’s syndrome) is usually defined as maternal edema associated to fetal hydrops [19]. Different fetal conditions have been related to mirror syndrome, although pathogenesis and pathofisiology of Ballantyne’s syndrome is currently unknown [19]. Mirror syndrome associated to large placental chorioangiomas has been described only a few times [20–23] and maternal edema has been always present, as was in our case. In addition, other clinical markers also been reported as oliguria, anemia, elevated liver enzymes, hypoproteinemia and hypokalemia were also present in our patient. Additional clinical signs and symptoms described in Mirror syndrome related to large chorioangiomas such as elevated blood pressure, proteinuria, elevated uric acid and creatinine, headache and visual disturbances, and low platelets were absent in our case, which made easier differential diagnosis with preeclampsia. As described elsewhere [19] mirror syndrome disappears shortly after fetal hydrops successful treatment, pregnancy termination or delivery, as in the patient presented here.

In the case described here, which presented with fetal anemia and severe hydrops, additionally complicated by maternal mirror syndrome, intrauterine transfusion and amniodrainage were performed. However, fetal condition got worse despite of the anemia correction. Finally, an emergency cesarean section, after thoracocentesis to optimise the neonatal resuscitation, was performed due to worsening of maternal and fetal condition and to prevent fetal demise. Current data and experience from clinical practice are still scanty to support the effectiveness of intrauterine therapy procedures in chorioangioma complicated cases, specially in cases with fetal hydrops, which led us to attempt a more conservative approach. However, our outcome raises the issue whether additional intrauterine clinical intervention, as intersticial laser, should have been performed to stop further deterioration of the fetal condition when progressive severe hydrops develops.

Written informed consent was obtained from the patient for publication of this report and any accompanying images, as it is our usual publication policy according to our Internal Review Board instructions.