Which test procedure is recommended if either parent carries tay-sachs, spina bifida, sickle-cell, down syndrome, muscular dystrophy, or rh disease?

Amniocentesis or amniotic fluid test or AFT refers to the prenatal diagnosis of chromosomal abnormalities and fetal infections. It is performed after 16 weeks of pregnancy. The fetal DNA from a small amount of cells from the amniotic fluid of the amniotic sac is sampled for genetic abnormalities by inserting a needle and extracting it. The fluid contains cells that are sloughed off by the fetus. They are separated from the amniotic fluid, grown in a culture and then microscopically examined for genetic and chromosomal abnormalities. The test is a reliable indicator of chromosomal abnormalities such as Down’s syndrome, spina bifida, muscular dystrophy, rh diseasetrisomy 13, trisomy 18, fragile X, Tay-Sachs disease, Hunter's syndrome and other metabolic disorders.