High Amniotic Fluid (Polyhydramnios): Causes, Symptoms And Treatment

High Amniotic Fluid

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The amniotic fluid acts as a cushion to the baby in your womb. It also helps in the development of the baby’s lungs, digestive tract, and muscles. Proper development of the baby is possible when the amniotic fluid levels are within the normal range. Too high or too little fluid volume may cause complications in pregnancy.

In this MomJunction post, we tell you what happens in the case of polyhydramnios or excess amniotic fluid in the womb. We also discuss its causes, symptoms, diagnosis, and more.

What Is Polyhydramnios?

Excess build-up of amniotic fluid around the growing baby is termed as polyhydramnios or hydramnios (1). According to the Fetal Medicine Foundation, UK, this condition occurs in one out of 100 cases (2).

Ideally, the doctor checks the amniotic fluid levels through an ultrasound. The normal volume of amniotic fluid should be between 500 and 1000ml. If it goes beyond this, there could be certain problems in the pregnancy.

What Are The Causes Of Polyhydramnios?

In most cases, it not clear why the amniotic fluid levels increase. However, some possible causes are:

  1. Diabetes: According to the University of Rochester Medical Center, women who had diabetes before pregnancy or have gestational diabetes could be at risk of hydramnios (1).
  1. Twin-to-twin syndrome: In this rare condition, the twins share a placenta. The baby that sends blood to its twin will have less amniotic fluid around, and the baby that receives will have a high volume of amniotic fluid or polyhydramnios (3).
  1. Birth defects: Congenital anomalies such as duodenal atresia or conditions relating to the heart or lungs (hydrops fetalis) may also lead to building up of the fluid, causing polyhydramnios (4).
  1. Others: Some other conditions, such as viral infections, fetal anemia, and kidney or heart problem, can also be responsible for increased amniotic fluid levels in the uterus (5) (4).

Detecting the condition early on is essential to avoid any pregnancy complications. Find out more about the symptoms that indicate an increase in the volume of amniotic fluid.

[ Read: Leaking Amniotic Fluid ]

Symptoms Of Polyhydramnios

Excess amniotic fluid can put pressure on the uterus and nearby organs. This could cause (2) (6).

  • Discomfort in the stomach
  • Shortness of breath
  • Contractions
  • Swelling in the abdominal wall and lower extremities
  • Change of fetal position
  • Enlarged uterus (than it is during pregnancy)

If these symptoms are overlooked, or if the condition is left untreated, the risks of certain pregnancy complications may increase.

Risks Related To Excess Amniotic Fluid

Polyhydramnios could be mild, moderate, or severe. Severe polyhydramnios is associated with the following complications (2) (6).

  • Too much fluid can expand your uterus and result in preterm labor
  • Early rupture of the amniotic sac
  • When amniotic fluid leaks, there could be placental abruption (detachment of the placenta from the uterus)
  • Umbilical cord prolapse (when the umbilical cord drops into the vagina)
  • Heavy bleeding after birth
  • Stillbirth

Timely diagnosis could help prevent these risks.

Diagnosis Of Polyhydramnios

Based on the checkup and the symptoms displayed, the doctor will recommend a fetal ultrasound. If the results hint at excess amniotic fluid, a detailed ultrasound is done (6).

There are two ways to measure the volume of the amniotic fluid.

  • One is AFV or amniotic fluid volume, which measures the deepest and single largest pocket of fluid. If this measure is equal to or more than 8cm, it is diagnosed as polyhydramnios.
  • The second method is AFI or amniotic fluid index, which is the sum of the largest pockets of different parts in the uterus. If this measurement is greater than 25cm, it suggests excess amniotic fluid volume.

AFI higher than 25cm and less than 29.9cm is considered mild polyhydramnios. AFI between 30cm and 34.9cm is moderate polyhydramnios, and AFI greater than or equal to 35cm is severe polyhydramnios (7).

Amniocentesis (amniotic fluid sample testing) and blood tests may also be recommended to know about the risks in detail. Nonstress test and biophysical profile could be prescribed to know the heart rate, movement, and breathing of your baby.

[ Read: Low Amniotic Fluid (Oligohydramnios ) ]

How Can Polyhydramnios Be Treated?

Mild cases of polyhydramnios rarely require treatment. However, weekly ultrasound scans are done to closely monitor the amniotic fluid index and the baby’s health. Even the size of the womb is measured to identify the risk of congenital disabilities.

But in severe cases of polyhydramnios, a few treatments are recommended to reduce the amniotic fluid level and keep your pregnancy safe. Treatment options may differ depending on certain factors such as the severity of the condition, its cause, symptoms, and gestational age (8).

  1. Medications: Based on the cause of excess amniotic fluid in the uterus, doctors prescribe medicine to reduce the fluid. For instance, if hydramnios is due to fetal condition, then medicine to treat that condition is prescribed. This, in turn, adjusts the fluid level.
  1. Amnioreduction: In this procedure, the doctor inserts a long needle inside the uterus to drain out the excess amniotic fluid. This procedure may cause a little discomfort in the abdomen.
  1. Delivery: In case of complications that seem risky for the mother’s or baby’s health, early delivery is scheduled.

Besides the treatment, following a few self-care measures can help.

Things To Do If You Have Polyhydramnios

Once the diagnosis of polyhydramnios is confirmed, try to be calm and talk to your doctor about it and clear any doubts you have.

  • Try to know the level of amniotic fluid in the uterus, to know if it is mild or severe.
  • Rest properly. If you are a working woman, plan and take your leaves to avoid stress.
  • Notice the changes or any new symptoms in your body and let the doctor know about it.
  • Talk about the treatment options and the birth plan.
  • Follow up with the doctor to understand your test results and check the progress after the treatment.

Can Polyhydramnios Cause Birth Defects?

Polyhydramnios or too much of amniotic fluid usually indicates that there could be a congenital anomaly or a birth defect in the baby, and may not necessarily cause it. Birth defects, however, could be responsible for causing polyhydramnios or too much of amniotic liquid.

If the doctor finds that there is too much amniotic fluid, an ultrasound or other tests could be done to analyze the risks.The treatment options are recommended based on the results.

[ Read: Water Break During Pregnancy ]

Is Polyhydramnios Dangerous For The Baby?

A severe case of polyhydramnios could increase the risks of preterm labor, placental abruption, infections, and stillbirth. But proper diagnosis and treatments in time can help in cutting down these risks.

Regular checkups during pregnancy are essential for every expectant mother. These help in figuring out problems early on, giving enough time to manage the issue. As polyhydramnios is not a common condition, there is no need to get too anxious about it. Even if the doctor suspects or diagnoses you with the condition, timely treatment and care can help minimize the risks, as discussed above.

Do you have any experiences to share? Do let us know in the comment section.


1. Hydramnios; University of Rochester Medical Center
2. Polyhydramnios; The Fetal Medicine Foundation
3. Twin-to-twin transfusion syndrome; C. S. Mott Children’s Hospital Michigan Medicine
4. Polyhydramnios treatment at Midwest Fetal Care Center; Children’s Minnesota
5. Polyhydramnios; Darthmouth-Hitchcock
6. Polyhydramnios; NCH Healthcare System
7. Polyhydramnios; Spectrum Health The Medical Group
8. A. Hamza, D. Herr, E. F. Solomayer, and G. Meyberg-Solomayer; Polyhydramnios: Causes, Diagnosis and Therapy; Geburtshilfe und Fraueneilkunde (2013)


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