Placental mesenchymal dysplasia, a case of intrauterine sudden death in a normal-sized fetus.

Introduction: placental mesenchymal dysplasia (PMD) is a rare placental anomaly characterized by placentomegaly and grape-like vesicles which resemble molar pregnancy.

Case: we report the case of 33-year-old woman (1-gravid) who visited our clinic at 11 weeks of gestation due to a suspected molar pregnancy. Ultrasound examination showed an enlarged placenta with multiple vesicular lesions. Maternal human chorionic gonadotropin level was normal and chorionic villus sampling showed a normal male karyotype (46 XY). The fetus exhibited no specific anomalies and fetal growth was normal during pregnancy with no signs of fetal suffering. At 31 weeks, the pregnancy ended owing to intrauterine fetal death (IUFD). The patient delivered a normal-sized male fetus (1800 g) with no definite anomalies. A pathological examination led to a diagnosis of placental mesenchymal dysplasia.

Conclusion: in the presence of placental ultrasound anomalies with no other sign of fetal suffering, the pregnancy should be considered at risk and, therefore, should be monitored carefully including the option of hospitalization.