Very Interesting Facts About Amniotic Fluid

01 February, 2020
Amniotic fluid has a very important role in fetal development and well-being during pregnancy. Besides being a protective agent, it stores nutrients and allows fetal musculoskeletal, gastrointestinal, and lung development.
 

Amniotic fluid is the fluid that surrounds the fetus during gestation inside the womb. It exerts a very important role in fetal growth and development. In this article, discover some very interesting facts about amniotic fluid that you might not have known.

Amniotic fluid composition

This fluid changes its composition as the pregnancy progresses. Furthermore, its volume increases as pregnancy progresses, generally until week 32. However, it begins to decrease at week 40.

Initially, it’s the result of osmotic gradients. In other words, it’s first formed by plasma from maternal blood and substances from the placenta, uterine membrane, and the surface of the embryo.

Then, once the fetus has developed urination and swallowing mechanisms, it’s mainly formed by:

  • Fetal urine.
  • Fluid from the lungs.
  • Oral and nasal secretions.
Very Interesting Facts About Amniotic Fluid

The fetus is continuously ingesting this liquid and, at the same time, expelling it through urine. This involves the regulation of the amount present in the amniotic sac, which grants the necessary balance.

Functions

Some of the most important amniotic fluid functions are:

 
  • Protective function against external trauma or shock.
  • Cushioning effect for the fetus and the umbilical cord in the womb.
  • Protection and defense against infection.
  • Deposit of food and growth factors for the fetus during pregnancy.
  • It helps maintain fetal temperature stable.
  • In addition, it contributes to lung maturation thanks to the presence of several enzymes.
  • Also, it allows fetal musculoskeletal, gastrointestinal, and lung development.

More facts about amniotic fluid: related pathologies

Alterations in the amount of fluid

During pregnancy, there can be variations in the amount of amniotic fluid, causing either too much or not enough fluid, for various reasons. Both are pathological:

  • Oligohydramnios. Amniotic fluid deficiency. This condition is associated with complications, such as:
    • Early labor induction.
    • Low birthweight.
    • Fetal bradycardia during delivery.
    • It can even cause fetal death.
  • Polyhydramnios. An excess of amniotic fluid. This condition is associated with complications, especially maternal, such as:
    • Gestational diabetes.
    • Hypertension during pregnancy.

Medical professionals usually detect these alterations by an ultrasound procedure to measure the volume of amniotic fluid. They do so through the amniotic fluid index (AFI).

To get this information, the expert divides the uterus into four unobstructed quadrants, which they measure in centimeters. A normal AFI is between 3 to 8 inches (8 and 21 cm).

Amniotic fluid embolism

Another related pathology is amniotic fluid embolism. It occurs when the amniotic fluid enters the woman’s blood. This is a very serious condition that can cause systemic hypoxia and coagulation abnormalities.

 
Very Interesting Facts About Amniotic Fluid

Meconium-stained amniotic fluid

Finally, we decided to highlight another aspect to consider. Meconium-stained amniotic fluid consists of the presence of meconium in the amniotic bag. Meconium is an infant’s earliest stool. Generally, it occurs after birth.

But sometimes, especially in babies who stay inside the womb for longer, it can occur before birth.

Typically, when the mother’s water breaks, the liquid is transparent or yellowish. If, on the other hand, it’s opaque, greenish, or thick, it indicates the presence of meconium. In that case, the specialist should assess the situation, as it can be an indicator of fetal distress.

Conclusion

Amniotic fluid has a very important role in the fetus’ development and well-being during pregnancy. Besides being a protective agent, it stores nutrients and allows musculoskeletal, gastrointestinal, and lung development. Any amniotic fluid alteration can cause major damage.

In addition, its prenatal study and analysis can detect congenital defects, such as chromosome disorders. This is performed through an amniocentesis. However, this technique is also associated with major risks that the medical professional must evaluate before performing it on a patient.

 

We hope you’ve found these facts about amniotic fluid to be interesting!

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