Analysis of midtrimester amniotic fluid for detection of open neural tube and ventral wall defects
AChE false-positive and false-negative results are more frequent at gestational ages of less than 13 weeks.
Do not use urine containers or tubes with rubber stoppers as rubber is toxic to amniocytes
Avoid contamination of amniotic fluid with maternal or fetal blood. As little as one drop of fetal blood can cause false-positive results during assay of amniotic fluid.
Ambient (preferred) - 7days
Refrigerated - NO
Frozen - NO
Acrylamide gel electrophoresis
AFP - An interpretive report will be provided
AChE - Negative