Gynaecology & Obstetrics The presence of increased levels of which of the following in amniotic fluid is an indicator of open neural tube defect in the fetus? A Phosphatidylesterase B Acetyl cholinesterase C Pseudocholineesterase D Butyrylcholineesterase 💡 Explanation The presence of increased levels of which of the following in amniotic fluid is an indicator of open neural tube defect in the fetus? ✓ Correct Answer: B. Acetyl cholinesterase