Everything You Need To Know About Amniotic Fluid – You Are Parent

Amniotic fluid is the fluid that surrounds the fetus during the gestation period in the mother’s womb. It performs a very important function in the growth and development of the fetus.

Composition of amniotic fluid

The composition of amniotic fluid changes as pregnancy progresses. Thus, its volume increases over time, usually up to the 32nd week, and from the 40th week it begins to decrease.

It is the result of osmotic gradients. In the beginning, it is formed from the plasma of the maternal blood and substances from the placenta, uterine membrane and the body surface of the embryo.

Then, after the fetus has developed urination and swallowing, it mainly forms:

• Fetal urine.
• Fluid from the lungs.

• Oral and nasal secretions. 

The fetus constantly ingests part of this liquid through the mouth; at the same time, it also expels it through the urine. This involves regulating the amount present in the amniotic sac, which gives it the necessary balance.

Functions

Some of the most important functions of amniotic fluid are:

• The protective function in the face of trauma  or external blows.
• A cushioning effect for the fetus and the umbilical cord in the maternal uterus.
• Protection and defense against infections.
• A deposit of food and growth factors for the fetus during gestation.

• It helps to maintain the constant temperature of the fetus.
• It contributes to the maturation of the lungs, thanks to the presence of several enzymes.
• The fluid supports the  development of the musculoskeletal, gastrointestinal and fetal pulmonary systems.

Pathologies related to amniotic fluid

Alterations in the amount of fluid

During pregnancy,  variations in the amount of amniotic fluid can occur – too much or too little – for a variety of reasons. These variations are pathological:

• Oligohydramnios: little liquid. The associated complications are as follows:
  • Premature onset of childbirth.
  • Low weight fetus.
  • Fetal bradycardia at the time of childbirth.
  • Possibility of fetal death.
• Polyhydramnios: excessive amount of fluid. It is associated with complications, especially maternal, such as:
  • Gestational Diabetes.
  • Hypertension at the time of childbirth.

These alterations  are generally detected through ultrasound measurement of the volume of amniotic fluid. This measurement is done through the Amniotic Fluid Index or ILA. To obtain this data, the uterus is divided into four parts and the free areas of the fetus and the umbilical cord are measured in vertical centimeters. A normal ILA is between 8 and 21 cm.

Amniotic fluid embolism

Another related pathology is amniotic fluid embolism. This is the entry into the mother’s blood stream of foreign matter, such as fetal meconium. This is a very serious problem that can cause systemic hypoxia, as well as changes in coagulation.

Meconium amniotic fluid

Finally, here is another aspect to take into account. We call  meconium amniotic fluid the presence of meconium in the amniotic sac. Meconium is the intestinal secretion of the fetus, that is, its first excrement. Usually, this evacuation occurs after birth.

Sometimes, and especially  in babies who spend more time in their mother’s womb,  this secretion can occur before they come out. We are talking, in this case, of liquid or tinted waters.

Normally, when the mother loses the waters, the liquid is transparent or yellowish. If, on the contrary, it is opaque, greenish and thick, this indicates the presence of meconium. In this case, the specialist should be called as  this can be an indicator of fetal distress.

Conclusion

Amniotic fluid has a very important function in the development and well-being of the fetus during pregnancy. In addition to being a protective measure against blows, it serves as a reservoir for nutrients and allows the development of the musculoskeletal, gastrointestinal and fetal pulmonary systems. Any alteration of this liquid can cause serious damage.

Its study and prenatal analysis are of great help in detecting congenital defects such as chromosomopathies. They are carried out through amniocentesis. However, this technique is associated with great risks that must always be carefully evaluated before performing it.