A 24 year old women presents at 30 weeks with a fundal height of 50 cm.Which of the following statements concerning polyhydramnios is true:

• A. Acute polyhydramnios always leads to labor prior to 28 weeks
• B. Maternal edema,especially of the lower extremities and vulva is rare
• C. Esophageal atresia is accompanied by polyhydramnios in nearly 10% of cases
• D. Complications include placental abruption,uterine dysfunction and postpartum hemorrhage