by EBSCO Medical Review Board


Oligohydramnios is a lower than normal level of amniotic fluid. This fluid supports and protects the baby. It also helps with growth. Low levels can lead to problems for the baby and mother.

Fetus in Utero, Amniotic Fluid
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In some people, the cause is not known. In others, it may be due to:

  • Birth defects
  • Problems with the fetus's urinary system
  • A problem with the placenta
  • A tear in the amniotic sac
  • Pregnancy that lasts past the due date
  • Problems in the mother, such as fluid loss, diabetes, or high blood pressure
  • Problems from some medicines

Risk Factors

Things that may raise the risk of this problem are:

  • Pregnancy past the due date
  • Health problems in the mother
  • Growth problems in the baby


Some people do not have symptoms. Others may notice a gush of fluid from the vagina. The fluid may also leak out slowly.

The mother’s belly may also be smaller than it should be.


The doctor will ask about your symptoms and health history. A physical exam will be done.

An ultrasound will be done to view the womb and fetus.

A measure of the amniotic fluid will be done. It will help to find out if the level is not normal.


The doctor will watch the mother and baby closely. The mother will need to drink more fluids. Tests will also be done to make sure the fluid level does not drop more. This may be all that is needed.

Some mothers may need:

  • Amnioinfusion—Fluid is injected into the space around the baby
  • Induced birth after 34 weeks


This problem cannot always be prevented. Proper prenatal care can help to find problems before they happen.


The American Congress of Obstetricians and Gynecologists 

American Pregnancy Association 


Health Canada 

The Society of Obstetricians and Gynaecologists of Canada 


American College of Obstetricians and Gynecologists. ACOG Practice Bulletin No. 175: Ultrasound in pregnancy. Obstet Gynecol 2016 Dec;128(6):e241.

Amniotic fluid abnormalities. EBSCO DynaMed website. Available at: Accessed August 24, 2021.

Low amniotic fluid levels: Oligohydramnios. American Pregnancy Association website. Available at: Accessed August 24, 2021.

Oligohydramnios. March of Dimes website. Available at: Accessed August 24, 2021.

Prenatal ultrasound screening. EBSCO DynaMed website. Available at: Accessed August 24, 2021.

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