title: Multiple marker screening for Down syndrome in the first trimester of pregnancy.
authors.forename: E M
authors.initials: EM
authors.lastname: Wallace
mesh_terms: D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood; D004314:Down Syndrome / Q000175:diagnosis*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008423:Maternal Age; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011296:Prenatal Diagnosis / Q000379:methods*; D012680:Sensitivity and Specificity
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human