Leaking Amniotic Fluid: Symptoms, What to Do & Causes

Updated in August 2023

Leaking amniotic fluid is usually characterized by the presence of a transparent, odorless liquid in your underwear that results in wetness. It usually occurs more than once a day.

Many women may mistake amniotic fluid leaks for urinary incontinence, which is generally common in pregnancy. Large amniotic fluid losses will usually be accompanied by a decrease in fetal movements.

If you suspect that you are leaking amniotic fluid in the first or second trimester of pregnancy, you are advised to proceed immediately to the emergency room. Great losses of amniotic fluid can interfere with normal fetal development and can be life-threatening to the baby, which is why any losses should be assessed promptly. 

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Main symptoms 

In most cases, leaking amniotic fluid can be easily mistaken for urine incontinence, which is common during pregnancy and happens due to the weight of the uterus on the bladder. Increased vaginal discharge can also look like leaking amniotic fluid.

Some signs that may indicate that amniotic fluid is leaking include:

  • Wet underwear with an odorless and colorless liquid;
  • Wet underwear more than once a day;
  • Decreased movements of the baby in the womb, when there has already been a great loss of fluid.

Pregnant women with risk factors such as high blood pressure, diabetes, or lupus are more likely to have amniotic fluid leakage, but it can happen to any pregnant woman.

What does amniotic fluid smell like and look like?

A good way to tell if the wetness in your underwear is amniotic fluid, urine or vaginal discharge is to use a panty liner and observe the characteristics of the fluid. Urine is normally yellowish and has a distinct odor, while amniotic fluid is transparent and odorless. Vaginal discharge is also odorless but normally has more of an egg white consistency.

What to do

Treatment for leaking amniotic fluid varies according to gestational age:

First and second trimester

Immediate medical help is vital, but treatment is usually done with weekly consultations with the obstetrician to assess the amount of fluid lost throughout pregnancy. Ultrasound can be used to measure the amniotic fluid within the gestational sac. Mild low levels of amniotic fluid will be monitored, and the doctor will likely advise bed rest and increased water intake. This will help to prevent further fluid loss and the emergence of other complications.

If there are no signs of infection or bleeding associated with fluid leakage, the woman can be monitored periodically as an outpatient. Outpatient visits usually involve checking body temperature and doing a blood count to assess for signs of infection or labor. Tests are also done to see if everything is okay with the baby, such as auscultation of the baby's heartbeat and fetal biometry.

Third trimester

Fluid leakage at the end of pregnancy is usually not serious, but if the woman is losing a lot of fluid, the doctor may choose to induce labor. If this loss occurs after 36 weeks, loss of amniotic fluid is usually a sign of rupture of the water sac. If you experience loss of fluid in the third trimester, proceed to the hospital to confirm whether labor has started.

Common causes

The causes for leaking amniotic fluid are not always known. However, it can happen as a result of a genital infection, therefore you should report any symptoms like burning when urinating, genital pain, or redness to your obstetrician if they appear.

Other causes that can cause amniotic fluid leakage or lead to a reduction in its amount include:

  • Partial rupture of the sac, in which the amniotic fluid begins to leak due to a small hole in the sac. This is more frequent in late pregnancy. Usually the opening closes by itself with rest and good hydration;
  • Problems in the placenta, in which it may not be producing enough blood and nutrients for the baby, who doesn't produce as much urine, resulting in less amniotic fluid;
  • Medication for high blood pressure, as they can decrease the amount of amniotic fluid and affect the baby's kidneys;
  • Fetal abnormalities: at the beginning of the second trimester of pregnancy, the baby may start to swallow the amniotic fluid and eliminate it through the urine. When amniotic fluid is lost, the baby's kidneys may not develop properly;
  • Twin-to-twin transfusion syndrome, also known as feto-fetal transfusion syndrome, which can happen in the case of identical twins, where one can receive more blood and nutrients than the other, causing one to have less amniotic fluid than the other.

Some medication, such as ibuprofen, can also decrease the production of amniotic fluid, so it is important to inform the obstetrician before any medication is started.