- Amniocentesis is an invasive procedure
- It examines the presence of chromosomal abnormalities
- It can cause risks including premature labor, miscarriage, and infections.
- The process helps the parents prepare for the child if any condition of disability exists
- It is also used for amniotic stem cell banking
Amniocentesis is the procedure of removing a very small amount of amniotic fluid using a needle and taking it to diagnose chromosomal abnormalities, fetal infections, and other similar medical issues.
Amniotic fluid is the liquid in the amniotic sac. It protects the fetus effectively and also acts as a medium to supply nutrients, water, and biochemical products from the mother to fetus. The amniotic fluid contains fetal tissues that can provide basic information about paternity, the gender of the fetus and presence of any chromosomal abnormalities.
Though amniocentesis is basically used for testing genetic disorders it is now also used for treatment. In the case of an excess amniotic fluid, the procedure is done to decrease the volume of fluid.
What is the procedure?
A sample of amniotic fluid is collected through injecting a needle into the amniotic membrane. An ultra sound scanner is used to determine safe passage to inject the needle. Usually, the procedure takes 45 minutes to 1 hour, though collecting the fluid needs just 5 minutes. As it is important not to harm the baby or the protective sac, the procedure is done with utmost care.
As per guidelines, an amniocentesis is performed during the 14th week to 20th week of pregnancy. It can also be performed as early as 11 weeks in certain cases. Amniocentesis is also used in the third trimester to know if any infections occurred after membrane rupture.
What all can be diagnosed through this test?
- Down’s Syndrome
- Trisomy 13 and Trisomy 18
- Genetic disorders like Cystic fibrosis
- Neural tube defects like Spina Bifida
- Anemia in the baby
- Maturity of the baby’s lungs
- Gender of the baby
- Paternity of the baby through DNA analysis
- Infection after a membrane rupture
As per the data provided by authorities, the test results of amniocentesis are accurate for about 99 percent. But the severity of genetic disorders or other defects cannot be assessed through this test.
What Leads to Amniocentesis?
1. Genetic testing:
If a prenatal screening test had indications of the presence of any genetic disorders, then an amniocentesis helps verify it or to get a clear picture.
If the pregnant mother experienced a chromosomal defect in the previous pregnancy.
Abnormal ultra sound findings can also lead to an amniocentesis.
Family history of genetic disorders
2. Evaluation of fetal lung maturity
It is mostly done to know the development of lungs in the fetus when a situation to deliver the baby soon through an induced labor, or C-section arrives.
3. To check for infections
In case of early rupture of amniotic membrane, an amniocentesis will be performed to know the presence of any infection.
If there exists a condition of increased amount of amniotic fluid the procedure is used to decrease the level.
What are the Risks of Procedure?
In general, amniocentesis is not recommended if the mother has infections like Sexually Transmitted Diseases, Hep B or C. The procedure can spread the disease to the fetus.
One in 400 cases of amniocentesis faces a miscarriage as per researches. Since it is an invasive procedure, the risks are higher.
- Preterm labor and birth
Chances of preterm labor and delivery are higher after amniocentesis.
- Amniotic fluid leaks
After the invasive procedure, amniotic fluid may leak as drops in some women. But, it usually stops within one week and does not pose a threat.
- Needle injury
Though a very rare concern, sometimes misfortune may play against us. The procedure may cause injury to the baby.
The invasive procedure may cause uterine infections rarely.
- Rh sensitization:
In rare cases, the baby’s blood cells may enter the mother’s blood stream.
A local anesthetic may be given to relieve the pain felt during the insertion of the needle. According to experts, it’s advisable to fill the bladder full if the amniocentesis is done between 14 to 20 weeks. If the procedure is done in the third trimester, between 32 to 34 weeks, it is recommended to empty the bladder.
Check for these signs after amniocentesis and contact your doctor immediately:
- If you have vaginal bleeding or fluid leaks
- Severe uterine cramping that lasts longer
- Unusual fetal movement pattern
As far as parents are concerned, if the fetus has any chromosome abnormalities or genetic disorders, they can prepare for it. The parents can aware themselves of supporting the baby efficiently. It can also help explore the scope of any treatments or interventions for any medical condition. Always clear your doubts about the procedure and stay free of anxieties.
Amniotic Stem cell banks:
The procedure can also be used to store amniotic stem cells for future purposes. Stored amniotic cells can help cure many congenital diseases and other medical conditions. It can also be used in developing any organ tissues as the body can accept its own cells easily. Hence stem cell donor issues can be resolved to an extent.