Amniocentesis is a procedure in which amniotic fluid from the uterus is removed to test for genetic abnormalities, and other developmental disorders of the fetus. The amniotic fluid is used to protect the baby during pregnancy and also contains fetal cells, hence can be used to find out information about the fetus. This prenatal test is necessary in case there is a family history of genetic disorders or there are some irregularities in the ultrasound. Amniocentesis can detect neural tube defects such as spina bifida and anencephaly and can also determine the sex of the baby. It is usually performed in the 15th – 18th week of pregnancy.
Before beginning an Amniocentesis, an ultrasound is performed in order to check the position of the fetus and placenta, the heart rate of the fetus and to find a suitable spot to inject the amniotic sac. A long needle is inserted at the identified place and an appropriate amount of amniotic fluid is withdrawn. The amniotic fluid removed is then sent to a lab for testing.
There are several risks involved in an Amniocentesis. There may be an infection or bleeding at the site of insertion of the needle. During performing the test, there are chances of the amniotic fluid to leak out of the vagina. If done in the second trimester of the pregnancy, there are also possibilities of miscarriage. During amniocentesis, there may be a needle injury which may harm the fetus. The baby’s blood cells may enter the mother’s blood while carrying out this procedure. In case the mother has HIV or infections like Hepatitis C, the infection may spread to the baby while carrying out an Amniocentesis.