Amniotic Fluid

Amniotic fluid contained in the amnion membrane is used to…

protect the fetus while enabling movement

Why would amniocentesis be performed?

Diagnosis of genetic and congenital disorders and assessment of fetal lung maturity

Why must the amniocentesis specimen be protected from light?

Bilirubin is light sensitive

How to differentiate Amniotic fluid and urine?

• Glucose and protein is normally present in amniotic fluid at moderate levels. It is low in urine

  • Creatinine and urea is same as plasma in amniotic fluid. It is high in urine

Why do creatinine levels begin to increase in late term pregnancy?

The fetus has begun to urinate

Normal amniotic fluid is…

colorless or pale yellow

What causes color of the fluid?

• yellow/amber: bilirubin

• Green: Meconium from fetal intestine

• pink/red: Blood or Hgb

All amniotic fluid is somewhat turbid, but it gets more turbid in…

late pregnancy

What bodies are used as a marker to determine how developed the baby’s lungs are?

Lamellar bodies

What are Lamellar bodies packed with?

Surfactant - substance that keeps lungs from collapsing after birth

If there is not enough Surfactant, the newborns can develop….

Respiratory Distress Syndrome

Lecithin

Major Pulmonary surfactant

Sphingomyelin

Phospholipid in cell membranes

A Lecithin/Sphingomyelin ratio of >2 indicates…

maturity

Why are blood and meconium unacceptable specimens?

Cause falsely high Lamellar body counts and falsely high Foam instability indexes

Bilirubin is undetectable in amniotic fluid until it is increased with…

fetal red blood cell hemolysis. The lily graph thing