Achecholinesteraseamncrto
This prenatal test measures enzyme levels in amniotic fluid to help detect certain birth defects, particularly neural tube defects like spina bifida.
{"The test analyzes enzyme activity in amniotic fluid collected during pregnancy","Elevated acetylcholinesterase levels may indicate open neural tube defects","It is typically used alongside other prenatal screening tests like AFP","The test requires amniocentesis to collect the fluid sample","Results help doctors assess fetal development and plan appropriate care"}
Key facts at a glance
- LOINC
- 45295-3
- Short code
- AChE/Cholinesterase Amn-cRto
- Synonyms
- AChE/Cholinesterase Amn-cRto
- Category
- chemistry
- Sample
- fluid
- Container
- Sterile tube
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Specimen volume
- 2-5 mL
- Stability
- Room temperature: 2h, Refrigerated: 24h
- Hemolysis max
- 300
- TAT
- 4–24 hours
- Order
- routine
What is this test?
The Acetylcholinesterase/Cholinesterase test measures the ratio of acetylcholinesterase to total cholinesterase enzymes in amniotic fluid. Acetylcholinesterase is an enzyme primarily found in nerve tissue and red blood cells. When an unborn baby has an open neural tube defect, such as spina bifida, this enzyme can leak from the fetal nervous system into the amniotic fluid, causing elevated levels that can be detected through this test.
How is the test performed?
This test requires a sample of amniotic fluid obtained through a procedure called amniocentesis. During amniocentesis, a thin needle is inserted through the abdomen into the uterus under ultrasound guidance to collect a small amount of amniotic fluid. The fluid sample is then sent to a laboratory where technicians measure the enzymatic activity levels. The procedure is typically performed between 15-20 weeks of pregnancy, though it can be done later if needed.
Why is this test important?
This test plays a crucial role in prenatal diagnosis. When combined with other screening tests like alpha-fetoprotein (AFP) testing, it helps healthcare providers identify potential neural tube defects and other abnormalities early in pregnancy. Early detection allows parents and medical teams to prepare for specialized care that may be needed after birth, including planning for surgery or other interventions. The test can also help rule out certain conditions when results are normal, providing reassurance to expecting parents.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Frequently asked questions
Does this test tell me if my baby has Down syndrome?
Is amniocentesis safe?
What happens if the test results are abnormal?
How long does it take to get results?
Sources
- 1
- 2
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy