Amniotic Fluid: An Overview 

Amniotic fluid happens to be the protective liquid found in amniotic sac of a pregnant woman. The development of the fetal baby takes place in the uterus. Amniotic sac is formed inside the uterus after 12 days of pregnancy. This sac holds the baby and the amniotic fluid for the rest of the pregnancy.
 

In the initial days, the amniotic fluid is just made of water obtained from the mother's body. This is the reason, pregnant women tend to become thirstier during the first trimester. Around 98% constituent of the amniotic fluid is water, while the remaining 2% count for salt and cells of the baby. It's after 4 months that fetus starts developing kidneys. Once the kidneys are formed, the fetus becomes capable of urinating. It now can swallow and digest the amniotic fluid. Ultimately, the amniotic fluid will fully turn to urine from the fetus.  Well, this may sound a bit yucky, but that's completely fine for the baby. Other than urine, this fluid also contains some of the nutrients, hormones, and the antibodies. 

Functions of the Amniotic Fluid  

The amniotic fluid has various functions which basically fall in two categories Viz. protection and development. The baby can not just float in the fluid, and roam around, the uterus also stays safe from blows. Amniotic fluid performs the following functions: 

• It lets the baby move around while it's in the developing stage. This movement encourages bone and muscle development.
• The fetus inhales and exhales the fluid thereby the fluid helps it in practicing breathing and also aiding in lung development.
• It helps in keeping the fetus nice and warm by guarding the heat in. It keeps the temperature consistent.
• The fluid protects from any blow likely to come to the uterus area. It cushions the blow if in case the mother falls.
• While the fetus swallows this fluid, it learns to practice the skills of using and developing the digestive system.
• It protects the umbilical cord from getting squeezed too hard. A big squeeze can possibly cut off the supply of nutrition from the mother to the baby.
• It even acts as a lubricant. 

Source of amniotic fluid

During the first trimester of pregnancy, this is primarily made up of the fluid supplied by the mother through placenta. However, in the second trimester, the baby turns the main producer of it. The two major sources of it are baby's urine and the fluid that get excreted from baby's lungs. 

The amount of amniotic fluid continues to mount as the baby gets bigger and the fluid increases till 32 weeks. It then stays constant, once the baby gets in the term i.e. 37 to 42 weeks, the levels start declining. In some cases, there can be excess of fluid; a condition termed as polyhydramnios or little of the fluid known as  oligohydramnios. Change in the fluid amount often risks the baby and the mother. For managing the pregnancy properly, great care has to be taken of the fluid. 

Measuring amniotic fluid

The amount of amniotic fluid is measured by an ultrasound scan. The amniotic fluid index, AFI, is calculated after taking many measurements. An AFI ranging between five centimeters- 25 centimeters is considered absolutely normal. If it goes less than five centimeters, the condition is called oligohydramnios while AFI above 25 centimeters is called polyhydramnios.

Oligohydramnios: Causes, Complications & Treatment 

Oligohydramnios is a condition that states there is very little amniotic fluid surrounding the fetus. The causes of oligohydramnios include: 

• ruptured membranes
• problem with baby's kidneys or the urinary tract
• issue with placental function

Complications of oligohydramnios

The problems linked with oligohydramnios tend to vary given the cause and pregnancy stage. In general, the earlier it occurs,  the more serious it turns to be. It can pose grave risks to the health of the baby including:

• impaired lung development
• club feet (talipes)
• preterm birth
• breech presentation
• infection in case the membranes are ruptured

Treatment of oligohydramnios

There stands no effective treatment for it. To improve the ultrasound imaging, one can consider the temporary replacement of fluid through a a needle, which is called amnioinfusion. 

Polyhydramnios: Causes, Complications & Treatment 

When there is excess of amniotic fluid, the condition is termed as Polyhydramnios. The causes of it are :

• fetal abnormalities
• maternal diabetes
• placental abnormalities

Complications of polyhydramnios

Considering the severity, this condition can double up the risk of certain pregnancy complications such as:

• premature birth
• disrupted membranes
• cord prolapse
• placental disruption (when the placenta gets separated from the uterine wall)
• postpartum haemorrhage (serious bleeding post baby's birth )
• wrong position of the baby (not coming of the head first)
• stillbirth
• It can even cause abdominal discomfort and breathing difficulties in woman owing to the increased abdominal size

Treatment of polyhydramnios

The management of this condition depends upon the cause. For instance, enhanced control of diabetes can lessen polyhydramnios. Some of the cases can even call for the removal of surplus amniotic fluid through a needle; the process is known as amniodrainage, in order to cut down the risk of ruptured membranes and also preterm birth. 

Keep a close watch on your amniotic fluid so that your pregnancy runs smoothly and there are no risks whatsoever!