Amniocentesis Amniocentesis (also referred to as amniotic fluid test or AFT) is a medical procedure used in prenatal diagnosis of chromosomal abnormalities and fetal infections, and also used for sex determination in which a small amount of amniotic fluid, which contains fetal tissues, is sampled from the amniotic sac surrounding a developing fetus, than the fetal DNA is examined for, such as The most common abnormalities detected are:- Down syndrome (trisomy 21). Edwards syndrome (trisomy 18). Turner syndrome (monosomy X).

Down syndrome (trisomy 21). Edwards syndrome (trisomy 18) Down syndrome (trisomy 21). Edwards syndrome (trisomy 18). Turner syndrome (monosomy X).

Amniocentesis Amniocentesis is performed between the 15th and 20th week of pregnancy; performing this test earlier may result in fetal injury. The term “early amniocentesis” is sometimes used to describe use of the process between weeks 11 and 13. Amniocentesis is usually done when a woman is between 14 and 16 weeks pregnant. Women who choose to have this test are primaril those at increased risk for genetic and chromosomal problems. This process can be used for prenatal sex discernment and hence this procedure has legal restrictions in some countries.

Procedure Before the start of the procedure, a local anesthetic can be given to the mother in order to relieve the pain felt during the insertion of the needle used to withdraw the fluid. After the local anesthetic is in effect, a needle is usually inserted through the mother’s abdominal wall, then through the wall of the uterus, and finally into the amniotic sac. With the aid of ultrasound- guidance, a physician punctures the sac in an area away from the fetus and extracts approximately 20ml of amniotic fluid. fetal cells are separated from the extracted sample. The cells are grown in a culture medium, then fixed and stained. Under a microscope the chromosomes are examined for abnormalities.

Procedure

Risks and drawbacks Complications of amniocentesis include :- preterm labor and delivery. respiratory distress, postural deformities. Chorioamnionitis. fetal trauma