title: Routine amniotic fluid alpha-fetoprotein measurement in 34,000 pregnancies.
abstract: Of 34,000 initial amniotic fluid samples, 0.7% had an alpha-fetoprotein level greater than or equal to +3 SD above the mean. The risk of an open neural tube defect or other serious fetal abnormality was 60% when alpha-fetoprotein levels measured greater than or equal to +3 and 86% for levels greater than or equal to +5 SD. In this series there were 72 open neural tube defects, and all were identified. The true false positive rate was 0.9 per 10,000 cases screened.
mesh_terms: D000110:Acetylcholinesterase / Q000032:analysis; D000328:Adult; D000649:Amniocentesis; D000653:Amniotic Fluid / Q000032:analysis*; D003951:Diagnostic Errors; D004589:Electrophoresis, Disc; D005260:Female; D006801:Humans; D008423:Maternal Age; D009436:Neural Tube Defects / Q000175:diagnosis* / Q000235:genetics; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D012306:Risk; D000509:alpha-Fetoproteins / Q000032:analysis*
chemical_list: D000509:alpha-Fetoproteins; D000110:Acetylcholinesterase