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What is Increase acetylcholinesterase in amniotic fluid indicates – and explain in detail?
Prenatal diagnosis of neural tube defect

In intra embryonic life, neural tube is open at both end and freely communicate with amniotic cavity.
Failure of closure of neural tube results in persistant of this communication.
This allows excretion of following fetal substances into amniotic cavity -


Alpha - fetoprotein
Acetylcholinesterase


These serve as biochemical marmkers for NTDs for prenatal diagnosis.