What are the symptoms of polyhydramnios?

about 1/3 of polyhydramnios is of unknown etiology, which is called idiopathic polyhydramnios. Most severe polyhydramnios may be related to fetal malformations and pregnancy complications. Fetal diseases include fetal malformations, chromosomal or genetic abnormalities, fetal tumors, and fetal metabolic diseases, which may cause polyhydramnios. Fetal malformations are associated, and neural tube defects and neural tube defects are more common. Polyhydramnios occur in about 10% of multiple pregnancies, like twin pregnancies, ten times more often than in single pregnancies. Complications of pregnancy, such as gestational diabetes, can also cause polyhydramnios due to abnormal glucose metabolism. Less common are placental and umbilical cord disorders, such as macrosomia and umbilical cord sail attachment.