title: Transvaginal ultrasonography in patients with human chorionic gonadotropin values less [corrected] than 1,000 mIU/mL: how often is the study diagnostic?
authors.forename: M
authors.initials: M
authors.lastname: Hauswald
authors.forename: M R
authors.initials: MR
authors.lastname: Williamson
mesh_terms: D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000097:blood*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D011237:Predictive Value of Tests; D011247:Pregnancy; D011271:Pregnancy, Ectopic / Q000097:blood / Q000000981:diagnostic imaging* / Q000191:economics; D012306:Risk; D014463:Ultrasonography / Q000191:economics / Q000379:methods; D014621:Vagina
chemical_list: D018997:Chorionic Gonadotropin, beta Subunit, Human