title: Effect of delayed initiation of gonadotropin in luteal long protocol on in vitro fertilization.
abstract: OBJECTIVE
  To evaluate whether delayed initiation of gonadotropin in luteal long protocol affected the outcome of in vitro fertilization (IVF).
  
  
  METHODS
  Prospective randomized study at the reproductive centre of a university-based hospital. Eighty-five subfertile women undergoing IVF embryo transfer after a standardized gonadotropin-releasing hormone agonists (GnRHa) long protocol. The patients were randomized into group A (stimulated 3 weeks after GnRHa administration) and group B (stimulated 2 weeks after GnRHa administration), according to the time of gonadotropin initiation after GnRHa-mediated pituitary suppression. The main outcome measures were clinical pregnancy and live birth rates.
  
  
  RESULTS
  There were no significant differences in baseline characteristics such as age, body mass index and basal follicle-stimulating hormone (bFSH) between the two groups. In group B, the days of gonadotropin stimulation were significantly greater than that in group A (p < 0.05), while the total dose of gonadotropin in group A was comparable to that in group B. Serum luteinizing hormone was lower and follicle-stimulating hormone higher in group A than in group B (p < 0.05) on initiation day. There were no significant differences in hormone profile measurements between the two groups. Moreover, the clinical pregnancy rate, implantation rate, live birth rate, miscarriage rate and moderate ovarian hyperstimulation syndrome rate were not significantly different between the groups.
  
  
  CONCLUSIONS
  Delay of gonadotropin stimulation in a standard long protocol may increase clinical efficiency, without significantly changing clinical outcome.
authors.affiliation: Department of Gynecology & Obstetrics, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou, China.
authors.forename: Haiyan
authors.initials: H
authors.lastname: Lin
authors.forename: Yu
authors.initials: Y
authors.lastname: Li
authors.forename: Lin
authors.initials: L
authors.lastname: Li
authors.forename: Qingxue
authors.initials: Q
authors.lastname: Zhang
authors.forename: Wenjun
authors.initials: W
authors.lastname: Wang
authors.forename: Xiaoli
authors.initials: X
authors.lastname: Chen
authors.forename: Dongzi
authors.initials: D
authors.lastname: Yang
mesh_terms: D000328:Adult; D002452:Cell Count; D004334:Drug Administration Schedule; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D005307:Fertilization in Vitro / Q000379:methods*; D006062:Gonadotropins / Q000008:administration & dosage*; D006801:Humans; D007246:Infertility / Q000453:epidemiology / Q000628:therapy*; D008183:Luteal Phase / Q000187:drug effects; D006080:Ovarian Follicle / Q000166:cytology / Q000187:drug effects; D016471:Ovarian Hyperstimulation Syndrome / Q000453:epidemiology; D010062:Ovulation Induction / Q000379:methods*; D011247:Pregnancy; D018873:Pregnancy Rate
chemical_list: D005300:Fertility Agents, Female; D006062:Gonadotropins