title: Measurement of human chorionic gonadotropin during early pregnancy: a comparison of two immunoradiometric assays.
abstract: Evidence of implantation following either in vitro fertilization and embryo transfer (IVF-ET) or gamete intrafallopian transfer (GIFT) was obtained by collecting blood on days 10, 12, 14, 16, and 18 after oocyte recovery (day 0), and retrospectively measuring human chorionic gonadotropin (hCG). This was done using immunoradiometric assays for hCG, manufactured either by Serono Diagnostics Ltd. (MAIAclone) or Diagnostics Products Corporation (IRMA-count). The analysis of 63 serum samples by both kits showed a good correlation (r = 0.99) but the Serono (y) method gave values which were consistently greater (y = 1.58x + 4.89) than those of the DPC (x) method. A comparison of the hCG profile of singleton pregnancies measured with either the Serono (n = 33) or DPC (n = 22) kits gave a similar relationship. These results suggest that great care must be taken when comparing results from different laboratories using different kits. Also, consideration must be given to the possible loss of a continuous database should a laboratory change kit.
authors.affiliation: Regional IVF Unit, St. Mary's Hospital, Manchester, UK.
authors.forename: P L
authors.initials: PL
authors.lastname: Matson
authors.forename: M C
authors.initials: MC
authors.lastname: Newman
authors.forename: D
authors.initials: D
authors.lastname: Morroll
authors.forename: S A
authors.initials: SA
authors.lastname: Troup
authors.forename: B A
authors.initials: BA
authors.lastname: Lieberman
mesh_terms: D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro; D015181:Gamete Intrafallopian Transfer; D006801:Humans; D015592:Immunoradiometric Assay / Q000379:methods*; D011247:Pregnancy; D011261:Pregnancy Trimester, First / Q000378:metabolism*; D011933:Reagent Kits, Diagnostic; D012015:Reference Standards
chemical_list: D006063:Chorionic Gonadotropin; D011933:Reagent Kits, Diagnostic