title: Letter: Alpha-fetoprotein in twin pregnancy.
mesh_terms: D000757:Anencephaly / Q000175:diagnosis; D005260:Female; D005326:Fetal Proteins; D005865:Gestational Age; D006801:Humans; D008431:Maternal-Fetal Exchange; D011247:Pregnancy; D011272:Pregnancy, Multiple; D011296:Prenatal Diagnosis; D011863:Radioimmunoassay; D014427:Twins
chemical_list: D005326:Fetal Proteins