Amniocentesis is mostly done in 16-18 weeks of pregnancy. During the pregnancy it is obvious that expected parents are worried about their new ones. They want to know each and every development of the baby and therefore this amniocentesis is done to know about baby’s disorder. This is only a test in which amino fluid is removed for testing which contains baby’s cells and proteins, this test tells about specific fetal disorder. In case any defect is found in baby, then parents may opt the way of abortion.
First time in 1919 a report from Hinkel first tell about release of amnio fluid from the patient. Menees in 1930 remove the amnio fluid from needle. But the very first time use of amnio fluid examination was done by Fuchs and Riis in 1956 in finding any fetal defect. John Edward in England in 1956 also examines the possibilities of hereditary disorders. Steele and Breg clearly demonstrated in 1966 that testing of amnio fluid is safe and suitable. Brock and Sutcliffe in 1972 found out the tremendous amount of alpha-fetoprotein (AFP) present in amniotic fluid with fetal defects. And from then onwards in laboratories amniocentesis test become rare to find out any inborn defects and errors.
The main purpose of amniocentesis is to check the development of the lungs in case of early delivery. This test identifies uterine infection. In this procedure technician first do the ultra sound in which he checks birth defects, checks the placenta, and evaluates the amniotic fluid levels. He also checks the date of pregnancy. In next procedure doctor insert the needle in the abdomen or uterus for taking out some amount of amino fluid. Then he takes this fluid for testing. Mostly this type of test is recommended for the woman who already has a child with this defect or has any family history. This type of test is also done in order to detect an abnormal alpha-fetoprotein. This test tells the levels of blood, too high or too low will detect the fetal abnormalities.
There are two type of amniocentesis:-
Mid trimester amniocentesis is done in second trimester in 15-18 weeks of pregnancy. As it involves some risks like miscarriages etc so doctors prefer to perform this procedure by the end of 15th week. As after 19-20 weeks it becomes difficult for abortion, if any defect is found so this week is found appropriate for amniocentesis.
Early amniocentesis is done in first trimester in 11-14 weeks. This is done in order to find out the development of foetal respiratory system. There is a larger chances of miscarriages in this stage because amnio fluid is present in very less amount and taking out even a little bit can be harmful. This type of amniocentesis is not preferable by parents.