Amniocentesis

A. What is it

there are actually a number of reasons you may get offered an amnio, the biggest is genetic testing but you can also get it done for diagnosis of infection or illness in your little one, treatment( might be done to drain fluid from the uterus if too much has built up in a condition called polyhydramnios) and fetal lung testing, if delivery is planned before the 39th week to help find out if your little ones lungs are mature enough for birth, but this is rarely done, it can also be done if your are over the age of 35, if there are certain genetic disorders that run in the family like sickle cell or cystic fibrosis.

Amniocentesis is a test to look at the fluid that surrounds your little one in the uterus. Amniotic fluid has cells and other substances that can give clues about the health of your little one.

This test may be done between weeks 15 and 20 to look at the little one's genes. It can also be used later in pregnancy.

Amniocentesis is often done around week 16 to see if a little one has certain genetic conditions. It can also tell the sex of a little one and help find certain neural tube defects like spina bifida or anencephaly.

Amniotic fluid has cells that have been shed by your growing little one. The cells are checked for the number and size of chromosomes. This can show if there are any problems that put the little one at risk for certain conditions, like Down syndrome, edward's syndrome, tay-sachs, or patau's syndrome. But this test can't find many common birth defects, such as cleft lip, cleft palate, or heart problems.

Testing is most often done as soon as possible so women and their families have time to think about their options.

This test may also be done later in pregnancy if your doctor thinks you may have an infection of the amniotic fluid (chorioamnionitis).

B. How it is done

For this test, a needle is put gently through your belly into your uterus. About 30 mL (2 Tbsp) of fluid is taken out and looked at.

Amniocentesis is usually carried out between the 15th and 20th weeks of pregnancy, but you can have it later if necessary.

It can be performed earlier, but this may increase the risk of complications of amniocentesis and is usually avoided.

During the test, a long, thin needle is inserted through your abdominal wall, guided by an ultrasound image.

The needle is passed into the amniotic sac that surrounds your little one and a small sample of amniotic fluid is removed for analysis.

The test itself usually takes about 10 minutes, although the whole consultation may take about 30 minutes.

Amniocentesis is usually described as being uncomfortable rather than painful.

Some women describe experiencing a pain similar to period pain or feeling pressure when the needle is taken out.

C. What is measured

the doctor will take a small sample of your amniotic fluid that surrounds your little one, only about 30mls worth.

D. How the results may influence the onset of labor

The first results of the test should be available within 3 working days and will tell you whether Down's syndrome, Edwards' syndrome, tay-sachs or Patau's syndrome has been discovered.

If rarer conditions are also being tested for, it can take 3 weeks or more for the results to come back.

If your test shows that your baby has a genetic or chromosomal condition, the implications will be fully discussed with you.

There's no cure for most of the conditions amniocentesis finds, so you'll need to consider your options carefully.

You may choose to continue with your pregnancy, while gathering information about the condition so you're fully prepared.

There is a risk of pre term labor if in later pregnancy, or a miscarriage if before 11 weeks