Gynaecology & Obstetrics Most useful maternal serum test used for distinguishing open neural tube defects and ventral wall defect in a fetus? A Carcinoembryogenic antigen B Sphingomyelin C Alpha-feto protein D Acetylcholinesterase 💡 Explanation Most useful maternal serum test used for distinguishing open neural tube defects and ventral wall defect in a fetus? ✓ Correct Answer: D. Acetylcholinesterase