ABSTRACT
Placental lakes appear as sonolucent areas in the placenta. They are often associated with fetal growth restriction due to placental insufficiency. However, they are commonly seen in normal pregnancy and are more common with advancing gestation and increasing placental thickness. Grannum et al. proposed a method of grading of placental appearance in 1979. The original classification of placental maturity was correlated to fetal lung maturity as assessed by the lecithin-sphingomyelin ratio. Intraplacental tumors are more difficult to recognize, and targeted ultrasound using color Doppler can help in identifying chorioangiomas in cases with a high index of suspicion, for example in unexplained polyhydramnios or hydrops with evidence of hyperdynamic fetal blood flow. Pregnancies complicated by placental chorioangioma are at increased risk of polyhydramnios and associated pre-term delivery. Apart from the effects of a hyperdynamic circulation, associations with chorioangioma include fetal growth restriction, placental abruption, and umbilical artery thrombosis.
