[Prenatal diagnosis of neural tube defects. Value of electrophoresis of cholinesterases].

Cholinesterase electrophoresis was performed in 802 amniotic fluids and its value in the detection of neural tube defects was compared with those of ultrasonography and amniotic fluid alpha-foetoprotein levels. Cholinesterase electrophoresis confirmed the ultrasonic diagnosis in 51 cases of neural tube abnormality and made it possible to diagnose neural tube defect in 6 other cases which had remained undetected by ultrasound and by alpha-foetoprotein level measurements. When our technique is used before the 28th week of gestation, false-positive results concern abnormalities which are easily detected by ultrasound (omphalocele, Bonnevie-Ullrich syndrome, sacrococcygeal tumour). We did not observe any false-negative result.