Ultrasound Findings and Clinical Outcomes in 23 Cases of Placental Mesenchymal Dysplasia

OBJECTIVE: To study the elements leading to a clinical suspicion of placental mesenchymal dysplasia (PMD), the course of the pregnancies, and the occurrence of obstetric and neonatal cornplications. PMD is a rare placental anomaly defined by the association of placentomegaly, macrocystic stem villi, and vascular abnormalities. STUDY DESIGN: We investigated all cases of PMD diagnosed from 2004-2014 in the 3 prenatal diagnosis centers of the university hospital network of Lyon, France. Clinical and ultrasound findings were collected for all cases. RESULTS: Twenty-three cases of PMD were identified. Intrauterine growth retardation was identified in 28.6% of the cases, intrauterine fetal death in 18.2%, and preeclampsia in 13%. Abnormalities included Beckwith Wiedemann syndrome in 25% of the cases. Two of the pregnancies (8.7%) progressed normally. Ultrasound assessments found in 90% of the cases enlarged, bulky, and thickened placentas associated with multiple large anechoic and avascular areas. CONCLUSION: To our knowledge, our study is the largest series published to date on the clinical findings of PMD. Ultrasound is currently the best tool to analyze the placenta early in pregnancy. Even when no antenatal fetal abnormalities are identified, it is nonetheless necessary to organize appropriate follow-up.