title: Increased progesterone/estradiol ratio on the day of HCG administration adversely affects success of in vitro fertilization-embryo transfer in patients stimulated with gonadotropin-releasing hormone agonist and recombinant follicle-stimulating hormone.
abstract: OBJECTIVE
  We investigated the influence of premature luteinization in in vitro fertilization using a long protocol of gonadotropin-releasing hormone agonist (GnRHa) and recombinant follicle-stimulating hormone (rFSH), taking ovarian response into account in the definition of premature luteinization.
  
  
  METHODS
  A total of 339 cycles of controlled ovarian hyperstimulation with rFSH and GnRHa were performed in 311 infertile couples. Premature luteinization was defined as a progesterone (P) to estradiol (E2) ratio of > 1 on the day of human chorionic gonadotropin (hCG) administration. The P/E2 ratio is calculated as: P (ng/mL) 1,000/E2 (pg/mL). Clinical outcomes were compared for the prematurely luteinized and non-prematurely luteinized groups.
  
  
  RESULTS
  The mean number of retrieved oocytes, recovered mature oocytes, embryos and top quality embryos were significantly higher in the non-prematurely luteinized group than in the prematurely luteinized group. Although fertilization rates and implantation rates were similar between the two groups, the clinical pregnancy rate was higher in the non-prematurely luteinized group than in the prematurely luteinized group.
  
  
  CONCLUSIONS
  Premature luteinization, defined as late follicular P/E2 ratio of > 1 in long GnRHa cycles with rFSH stimulation, adversely affected ovarian responses and clinical outcomes. It seems unrelated to preovulatory luteinizing hormone (LH) elevation and LH/hCG content of gonadotropins and could be associated with poor ovarian response and the presence of dysmature follicles.
authors.affiliation: Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan.
authors.forename: Yu-Che
authors.initials: YC
authors.lastname: Ou
authors.forename: Kuo-Chung
authors.initials: KC
authors.lastname: Lan
authors.forename: Shiuh-Young
authors.initials: SY
authors.lastname: Chang
authors.forename: Fu-Tsai
authors.initials: FT
authors.lastname: Kung
authors.forename: Fu-Jen
authors.initials: FJ
authors.lastname: Huang
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000008:administration & dosage; D004624:Embryo Transfer; D004958:Estradiol / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro; D005498:Follicular Phase / Q000502:physiology*; D006801:Humans; D034461:Luteinization; D054315:Oocyte Retrieval; D016471:Ovarian Hyperstimulation Syndrome / Q000503:physiopathology; D010053:Ovary / Q000503:physiopathology; D011374:Progesterone / Q000097:blood*; D012189:Retrospective Studies
chemical_list: D006063:Chorionic Gonadotropin; D011374:Progesterone; D004958:Estradiol