title: A highly sensitive electrochemiluminescence immunoassay for detecting human embryonic human chorionic gonadotropin in spent embryo culture media during IVF-ET cycle.
abstract: OBJECTIVE
  To investigate the stability and repeatability of electrochemiluminescence immunoassay (ECLIA) for beta-hCG detection in embryo spent culture media. To evaluate the correlation between the viability of preimplantation embryo and beta-hCG profile by the new assay.
  
  
  METHODS
  In a retrospective study, a total of 357 spent culture media from day1 to day5 were individually collected and quantified by ECLIA. The blank controls and reliability test were performed with normal saline/pure culture media.
  
  
  RESULTS
  1) There was no detectable amount of beta-hCG in blank controls. A high degree of linearity (R(2) = 0.995) was found in this study; intra-assay and inter-assay coefficient of variation were 4.87 % and 6.25 %. 2) A significantly higher concentration of beta-hCG was found at day5 group than it at day3 group, both in total samples (1.47 ± 0.68mIU/ml vs 0.55 ± 0.32mIU/ml) and in homologous embryo samples (1.43 ± 0.91mIU/ml vs 0.52 ± 0.23mIU/ml). 3) There was a positive correlation between beta-hCG concentration and implantation rate (r = 0.559 at day3 and 0.535 at day5) or blastocyst morphological grading (r = 0.411).
  
  
  CONCLUSIONS
  ECLIA may be an optimal choice for detecting beta-hCG in spent culture media to assess embryo viability, indicating secreted beta-hCG as a useful biomarker for embryo selection in IVF-ET procedure.
authors.affiliation: Human Reproductive Center, the First Affiliated Hospital of Sun Yat-Sen University, No.58 Zhongshan 2nd Road, Guangzhou, China.
authors.forename: Chen
authors.initials: C
authors.lastname: Xiao-Yan
authors.forename: Li
authors.initials: L
authors.lastname: Jie
authors.forename: Jiang
authors.initials: J
authors.lastname: Dang
authors.forename: Li
authors.initials: L
authors.lastname: Tao
authors.forename: Liu
authors.initials: L
authors.lastname: Xin-Ru
authors.forename: Zhuang
authors.initials: Z
authors.lastname: Guang-Lun
mesh_terms: D015415:Biomarkers / Q000737:chemistry; D001755:Blastocyst; D018997:Chorionic Gonadotropin, beta Subunit, Human / Q000302:isolation & purification* / Q000378:metabolism; D003470:Culture Media / Q000737:chemistry* / Q000378:metabolism; D010064:Embryo Implantation; D004624:Embryo Transfer; D005307:Fertilization in Vitro; D006801:Humans; D007118:Immunoassay; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; D018997:Chorionic Gonadotropin, beta Subunit, Human; D003470:Culture Media