Placental mesenchymal dysplasia (PMD) is a benign condition that can be confused with a molar pregnancy by ultrasound scanning and gross examination. Unlike molar pregnancy, the incidence of PMD is rare and has a reported incidence of 0.02%.

It is a rare placental anomaly characterized by placentomegaly and grape-like vesicles resembling molar pregnancy. PMD usually features a normal fetus. It is also called pseudo-partial mole. But fetal IUGR and IUD are quite common with PMD. 

Distinguishing PMD from its mimics, especially molar pregnancy is important for preventing unnecessary termination of pregnancy.