Placental Mesenchymal Dysplasia With Normal Placental Growth Factor Levels Complicated by Fetal Giant Liver Cyst and Anemia.

A case is presented of a 27-year-old woman who was referred to our Maternal Fetal Medicine Center following the detection of a multi-cystic placenta on a routine morphology scan. Ultrasound at our unit confirmed the presence of a diffusely cystic placenta and a well-grown and structurally normal fetus. The patient's placental growth factor (PlGF) level was found to be within normal limits. At 23 weeks, an enlarging hepatic cyst was identified in the fetus and was monitored through serial imaging. A multidisciplinary team was involved, including neonatal intensivists and pediatric surgeons. The patient underwent an emergency cesarean section at 30+4 weeks of gestation after presenting with preterm labor and concerns of fetal deterioration. She delivered a live-born female infant of normal birth weight. However, the neonate required immediate resuscitation with multiple blood product transfusions, likely due to complications from the known giant hepatic cysts. She was transferred to a quaternary neonatal unit for further management. Genetic testing excluded Beckwith-Wiedemann syndrome, which had been an antenatal differential. The neonate was discharged 2.5 months later after multiple drainages of her cysts, which were benign on fluid cytology. Our case highlights the complexity of placental mesenchymal dysplasia (PMD) and the importance of early multidisciplinary care to achieve the best possible outcome. The study also underlines the need for further research into the prognostic reliability of PlGF levels in PMD.