Use of Amniocentesis For Detecting Lung Maturity

By Ashley | February 26, 2010

Amniocentesis is a type of prenatal diagnosis wherein a needle is introduced into the uterus of the woman to remove a small quantity of amniotic fluid, for the purpose of screening. The withdrawn amniotic fluid is generally used to test certain health conditions or screen for genetic defects in the baby.

However, examining for birth defects is not the only reason amniocentesis is carried out. In some cases, an amniocentesis is performed towards the final stages of pregnancy to determine if the baby’s lungs have developed fully for the baby to commence breathing on its own soon after delivery. Amniocentesis for lung maturity could also be conducted if the medical practitioner is looking at an early delivery of the child. This could be due to medical reasons such as pre-eclampsia (unnatural state in pregnancy distinguished by high blood pressure, fluid retention and proteinuria, gestational diabetes, or any other medical conditions that may require prompt attention from the doctor. Under such medical circumstances, the doctor might suggest an early induction or an elective cesarean and hence opt for an amniocentesis to examine if the baby’s lungs are ready for the cesarean.

Unlike the risk that amniocentesis carries during early pregnancy and the second trimester, the amniocentesis for lung maturity during the latter stages of pregnancy is an easy and safe procedure. During the latter stages of pregnancy, the uterus is larger and hence it is easier to carry out the procedure without any complications for the mother and the baby. Most medical experts believe that an amniocentesis for fetal lung maturity must be performed if an elective cesarean has to be conducted before 39 weeks.

It is believed that babies born by elective cesarean stand at a much higher risk of developing substantial respiratory disorders. This is mainly because they do not have the benefit of birthing labor to get them ready for breathing on their own outside the uterus. A number of babies born by elective cesarean procedure tend to suffer some degree of respiratory disorders especially if the baby has been born between 37 and 38 weeks. In some cases these respiratory disorders can be extremely serious and even fatal.

When examining for fetal lung maturity in the final stages of pregnancy, the doctor might also recommend checking quantities of phosphatidyl glycerol (PG) along with the Lecithin/Sphingomyelin ratio (L/S ratio) in the amniotic fluid. Medical experts believe that lung maturity can be assessed more precisely if both L/S and PG levels are carried out. However it is important to remember that, like all other medical tests and screenings, amniocentesis for lung maturity could also bring about false positive results