Understanding the amniotic fluid and its function

Amniotic fluid is a fluid that protects and sustains as the fetus grows in the womb. Amniotic fluid is produced after the amniotic sac is formed or about 12 days after fertilization. The function of amniotic fluid is very vital for the fetus. Among other things, to protect the fetus from impact, to help the development of the legs, muscles, lungs, and digestive systemfetus.

Amniotic fluid is located in the amniotic sac. The color of the amniotic fluid is clear and slightly yellowish, but looks clear and odorless. It is in the amniotic fluid that the fetus floats, breathes, and moves.

The fetus also swallows amniotic fluid, excretes it as urine, then swallows it again. This aims to maintain the stability of the volume of amniotic fluid. The volume of amniotic fluid that is too much or too little can harm the pregnancy.

Amniotic fluid composition and volume

Amniotic fluid is composed of nutrients, hormones, and immune-forming cells that are useful for supporting fetal development. At 20 weeks of gestation, the composition of amniotic fluid is dominated by fetal urine.

The volume of amniotic fluid will continue to increase during pregnancy. However, when the gestational age reaches 38 weeks, the volume decreases to prepare for birth. Here's an estimate of the normal volume of amniotic fluid:

• 60 milliliters (mL) at 12 weeks of gestation.
• 175 milliliters (mL) at 16 weeks of gestation.
• 400–1,200 milliliters (mL) between 34-38 weeks of gestation.

Amniotic fluid volume can be too muchpolyhydramnios) or too little (oligohydramnios). Both of these conditions are dangerous for the development and safety of the fetus. Therefore, consult a gynecologist to determine the normal volume of amniotic fluid. The doctor will perform an examination with a pregnancy ultrasound to assess whether the volume of amniotic fluid is appropriate for the gestational age.

Amniotic fluid function

The important functions of amniotic fluid include:

• Provides room for movement for the fetus

  Amniotic fluid allows the fetus to have room to move. The fetus that moves frequently indicates that it is getting enough nutrients and oxygen.

• Supports muscle and bone development

  The movement of the fetus in the womb helps to form and increase the strength of the muscles and bones of the little one.

• Maintain ideal temperature

  The sac and amniotic fluid maintain the ideal temperature to keep the fetus comfortable. The temperature of the amniotic fluid is usually slightly higher than the mother's body, which is around 37 degrees Celsius.

• Detect genetic disorders

  Under certain conditions, the doctor may suggest genetic testing through a sample of the amniotic fluid in the mother's womb. This examination is called amniocentesis. This can be done because the amniotic fluid contains pieces of fetal skin cells. Amniocentesis should be performed before entering the second trimester of pregnancy.

• Protects from impact

  Amniotic fluid protects the fetus from shocks, impacts, or pressure on the mother's stomach.

• Helps lung development

  The fetus does not breathe the way we breathe. The fetus depends on the mother's breathing to receive oxygen. At 10-11 weeks of gestation, the fetus begins to inhale a small amount of amniotic fluid. Although inhaling, the movement is more like swallowing. This activity helps the development of the lungs. By the age of 32 weeks of pregnancy, the fetus will begin to practice breathing movements which are a combination of swallowing and lung contractions.

• Helps the development of the digestive system

  Swallowing amniotic fluid plays an important role in the development of the fetal digestive system. Difficulty swallowing amniotic fluid can result in too much amniotic fluid volume, which leads to the risk of pregnancy complications.

• Protects from infection

  Amniotic fluid plays a role in protecting the fetus from infection by stopping the growth of certain types of bacteria.

The amniotic sac will generally rupture before birth. When your baby is ready to be born, amniotic fluid will flow from the vagina. After that, you may experience firmer, more regular contractions. See a doctor right away if your membranes rupture prematurely, your water is thick green and smells bad, or you have a fever just before delivery.