Things to know

Amniotic fluid is a clear, slightly yellow-coloured liquid that develops around the fetus during pregnancy. It is a protective liquid that forms inside the amniotic sac nearly after 12 days of conception. The function of amniotic fluid is to protect the unborn baby from infections, umbilical cord compressions, injury and temperature changes in the body. It also allows the safe movement of the fetus in the womb. Additionally, amniotic fluid supports the development of your baby’s digestive and respiratory systems. 

According to the Amniotic Fluid Index measurement, the amount of amniotic fluid is 800 mL (greatest at 34 weeks of gestation). By full-term pregnancy, that is, by 40 weeks of gestation, the amniotic fluid is about 600 mL. 

Low amniotic fluid is a condition in which the amniotic fluid is at lower levels than expected as per your baby’s gestational age. This condition is medically known as oligohydramnios.  

Low amniotic fluid can cause various health problems in your fetus affecting your baby’s development. This condition can also increase your chances of pregnancy and birthing complications. Low amniotic fluid can also be an indicator of an underlying condition. 

Low amniotic fluid symptoms are more prevalent during the last trimester of pregnancy. It is not always possible to identify when you may have low amniotic fluid. Your healthcare provider may suspect that you may have this condition based on the following low amniotic fluid symptoms include:

• Leaking of fluid from the vagina 
• Small uterus wall 
• Fewer movements of the baby felt by the mother 
• Considerably less weight gain 

Based on these symptoms, your healthcare provider may order an ultrasound scan to measure your amniotic fluid index (AFI). 

There are no exact and identifiable low amniotic causes that we know of. Several factors contribute to low amniotic fluid causes:

The small size of the baby

A baby who is considerably smaller in size will produce less amount of amniotic fluid leading to oligohydramnios. 

Maternal health issues 

Underlying health concerns in the mother before or during pregnancy can also lead to low amniotic fluid. Common conditions contributing to this illness are diabetes, hypertension, preeclampsia and lupus. 

Placenta problems 

Several problems with the placenta including a partial abruption (peeling away of placenta from the inner wall of the uterus) can cause low amniotic fluid. 

Premature rupture of membranes 

It is common to experience leaking of fluid due to ruptured membranes. This condition can happen at any point in your pregnancy. However, it is one of the less common amniotic fluid causes. 

Carrying multiples

Your risk of low amniotic fluid increases when you are expecting twins or triplets. It is more common in the case of twin-to-twin transfusion syndrome (a condition in which one twin has more amniotic fluid than the other). 

Increased gestational age 

You are about two weeks past your due date, you can expect low amniotic fluid. 

Dehydration 

Low amniotic fluid can also develop due to lesser consumption of fluids resulting in dehydration. 

Congenital anomalies 

Birth defects are a common cause of oligohydramnios. Fetal abnormalities, especially those affecting the baby’s kidneys or urinary tract can lead to this condition.  

It is common to experience a gradual dip in amniotic fluid towards the end of pregnancy till it averages about 600 mL. However, low amniotic fluid during the first and second trimesters can have potential complications for the baby. 

Common low amniotic fluid complications include:

• Deformities caused by womb compressions 
• Premature birth 
• Loss of pregnancy 
• Stillbirth 
• Infection 

Low amniotic fluid complications during the third trimester include:

• Umbilical cord compression 
• Fetal growth restriction 
• Underdeveloped lungs causing respiratory problems 
• Increased risk of C-section delivery 
• Increased need for an early delivery 
• Increased risk of infection 

An ultrasound scan helps in the diagnosis of low amniotic fluid. Your doctor will examine the level of amniotic fluid and measure it based on the gestational age of your baby. 

The low amniotic fluid treatment is dependent on the stage of your pregnancy, the health of the fetus and whether you have any associated complications. You will be monitored closely to devise the treatment protocols. 

If you are close to 36-37 weeks pregnant, the safest option for the low amniotic fluid treatment is delivery. If the gestational age is less than 37 weeks,  your doctor will ensure that your baby continues to grow normally.

You may receive care in the form of labour induction or cesarean delivery. Babies delivered as a result of preventing low amniotic fluid complications may also be treated at the neonatal intensive care unit (NICU). 

You cannot prevent oligohydramnios but there are some short-term steps you can take to manage low amniotic fluid symptoms. 

• Drink plenty of water 
• Getting extra rest 
• Continuing close monitoring of amniotic fluid levels 
• Scheduling your delivery early 
• Managing your blood sugar and blood pressure levels