The Connection Between Amniotic Fluid and Baby’s Lung Development

Amniotic fluid plays a crucial role in the development of your baby. This fluid also acts as a cushion to protect them. Your baby’s lungs may not develop properly without enough of this fluid. This blog explains how amniotic fluid supports the development of lungs and what problems can arise if the levels fluctuate too much outside the normal ranges.

Pregatips
You may be aware that your baby floats in a fluid inside the womb, but it is crucial for other reasons as well. Amniotic fluid is a special liquid that protects, nourishes and helps your baby grow. The most important function of this fluid is to support lung development in your baby. Understanding how amniotic fluid supports lung health and what could go wrong if levels are not right will help you seek medical care on time.

What is Amniotic Fluid and Why is it Important?

Amniotic fluid is a clear or slightly yellow liquid that fills the amniotic sac in which your baby grows. This liquid starts forming about 12 days after conception and rises steadily around 34-36 weeks of pregnancy. You may carry about 800-1000ml of fluid when you reach the end of the term.
Amniotic fluid plays the following roles while also protecting your baby.
  • Protects your baby from bumps and injuries.
  • Maintains the temperature in the womb.
  • Helps with movement, allowing the muscles and bones of your baby to develop properly.
  • Your baby practises breathing and swallowing with the help of this fluid.

How Does Amniotic Fluid Help Your Baby’s Lungs Develop?

The lungs develop fully in pregnancy and become roughly mature after 36 weeks (“Foetal lung maturity” is a spectrum and may vary by week and condition; some infants still need support if born before 38–39 weeks).
  • Fluid Breathing Practice: Your baby inhales and exhales amniotic fluid, which helps expand the lung air sacs (alveoli). This practice prepares the lungs for breathing air after birth.
  • Nutrient Transfer: This fluid provides your baby with nutrients, hormones, and growth elements, which support the development of lung tissue.
  • Balanced Pressure: Normal fluid levels prevent the lungs from collapsing or becoming too stiff.

What Happens if Amniotic Fluid Levels Are Too Low?

When the amniotic fluid levels drop below 500ml in late pregnancy, it is referred to as oligohydramnios. This condition can cause the following problems.
  • Poor lung growth (pulmonary hypoplasia) occurs when the lungs remain underdeveloped
  • Reduced movement, leading to joint or bone problems
  • Umbilical cord compression can lower the oxygen supply

Low fluid levels are more concerning in early or mid-pregnancy stages, when the lungs are still developing. Doctors can manage this condition safely if it occurs in the later stages. Just be mindful of the following warning signs.
  • Leaking fluid (sudden wetness in your underwear)
  • Baby’s movements feel weaker than usual
  • Measuring smaller than expected during checkups

What Happens if Amniotic Fluid Levels Are Too High?

Polyhydramnios is a less common condition characterised by abnormally high amniotic fluid levels. It may stretch your uterus more and lead to the following problems.
  • Preterm labour
  • Breathing problems for the baby after birth
  • Increased risk of the cord slipping out (cord prolapse)

Sometimes, Polyhydramnios may be a result of gestational diabetes, or the baby may have problems with swallowing or an anatomical defect in the digestive tract. The symptoms of this condition are listed below.
  • Rapidly growing belly size
  • Shortness of breath for you
  • Swelling in your feet or legs

When Should You See a Doctor About Amniotic Fluid?

You should always be aware of the changes occurring in your body during pregnancy, so contact your doctor if you experience any of the following signs.
  • Leaking or gushing of fluid
  • Baby is moving less than usual
  • Suddenly, severe belly pain
  • Extreme swelling or shortness of breath
Your doctor may recommend an ultrasound scan to check the Amniotic Fluid Index (AFI) and your baby’s health.

How Can You Maintain Healthy Amniotic Fluid Levels?

Maintaining the fluid levels can be challenging, but you can take other steps to support your baby’s development.
  • Stay hydrated: Drink 8–10 glasses of water daily.
  • Manage health conditions: Keep blood sugar levels under control if you have diabetes.
  • Attend regular prenatal visits: This helps detect problems early.
  • Rest on your left side: This position helps improve blood flow to the placenta, which can aid in reducing fluid levels.

Emotional and Social Aspects You Should Know

Pregnancy can be overwhelming due to the numerous changes that occur simultaneously. When you hear that your amniotic fluid is not in normal ranges, it can only add to this overwhelming experience. Keep the following points in mind to overcome this situation.
  • Many mothers go through this situation, so you are not alone. Most babies do well with proper care.
  • Openly discuss your emotions with your partner and family for emotional support.
  • Discuss any concerns you have about your baby with your doctor.

Checklist: What to Do Next if You’re Concerned?

  • Drink enough water every day
  • Track your baby’s kicks and movements
  • Note any leaking fluid or unusual symptoms
  • Keep all prenatal appointments
  • Discuss any health conditions (like diabetes or high blood pressure) with your doctor
  • Ask your doctor about your amniotic fluid index during ultrasounds
Amniotic fluid is a protective cushion for your baby, but it is also essential for their lung development. It also helps your baby practise breathing and swallowing inside the womb. This practice helps your baby thrive after birth. Your baby’s lungs may not work if the levels are too high or too low. You can take various measures and follow a healthy lifestyle to maintain the fluid levels.

Whether you’re pregnant, a new mom, or navigating postpartum, you don’t have to do it alone. Join our support group to connect, share, and support one another.

FAQs on The Connection Between Amniotic Fluid and Baby’s Lung Development


  1. Can drinking water really increase amniotic fluid levels?
    In some mild cases, drinking water can help increase your fluid levels, but medical treatment is necessary when levels are too low.
  2. What week of pregnancy do the baby’s lungs fully develop?
    Lungs usually develop at the later stages of pregnancy and mature nearby around 36 weeks of pregnancy. Babies born before this time may require breathing support.
  3. Is it possible to control amniotic fluid levels through diet?
    Diet is only one factor among many that can support your overall health during pregnancy. Other factors include eating healthy foods, drinking water regularly, and managing health conditions.
Disclaimer: Medically approved by Dr Prashant Laxmanrao Ramtekkar, Consultant- Paediatrician and Neonatologist, Motherhood Hospitals, Pune