amniocentesis

n. A prenatal diagnostic tool, the amniocentesis allows for screening of genetic abnormalities. This procedure consists of a needle's being inserted into the abdomen wall of the pregnant woman to obtain a sample of amniotic fluid. An ultrasound is used in conjunction with this needle insertion to protect the developing fetus. Within the amniotic fluid are cells that can be grown in a laboratory dish and analyzed to determine genetic information. This procedure typically cannot occur until approximately 16 weeks of gestation and then can require an additional 3 weeks for growth and testing of cells.  -SRB