Polyhydramnios is a condition in which there is too much fluid in the amniotic sac, the sac that holds the developing baby (fetus). This liquid is called amniotic fluid, and it surrounds the fetus throughout pregnancy.
Polyhydramnios can be caused by:
- Problems with the baby's nervous system or gastrointestinal tract.
- Genetic disorders or birth defects.
- Multiple pregnancy (twins or more). It occurs in up to 5 out of 100 twin pregnancies.1
Sometimes the cause of polyhydramnios may not be found.
Polyhydramnios increases the risk of:
- Premature breaking (rupture) of the amniotic sac.
- Premature labor.
Severe polyhydramnios may be treated with medicine, such as indomethacin. Excess fluid is sometimes removed through a needle that is inserted through the mother's abdomen into the amniotic sac (amniocentesis).