title: GnRH agonist during luteal phase in women undergoing assisted reproductive techniques: systematic review and meta-analysis of randomized controlled trials.
abstract: OBJECTIVE
  To identify, evaluate and summarize the available evidence regarding the effectiveness and safety of administering a gonadotropin releasing hormone (GnRH) agonist during the luteal phase in women undergoing assisted reproductive techniques.
  
  
  METHODS
  In this systematic review and meta-analysis, we searched for randomized controlled trials (RCTs) comparing the addition of a GnRH agonist during the luteal phase, compared with standard luteal-phase support. We searched seven electronic databases and hand-searched the reference lists of included studies and related reviews. Our primary outcome was live birth or ongoing pregnancy per randomized woman. Our secondary outcomes were clinical pregnancy per randomized woman, miscarriage per clinical pregnancy, adverse perinatal outcome and congenital malformations.
  
  
  RESULTS
  The evidence from eight studies examining 2776 women showed a relative risk (RR) for live birth or ongoing pregnancy of 1.26 (95% CI, 1.04-1.53; I(2) = 58%). Sensitivity analysis when excluding the studies that did not report live birth and those at high risk of bias resulted in one study examining 181 women with an RR of 1.07 (95% CI, 0.73-1.58). Subgroup analysis separating the studies by single/multiple doses of GnRH agonists or by ovarian stimulation with GnRH agonist/antagonist was unable to explain the observed heterogeneity. The quality of the evidence was deemed to be very low: it was downgraded because of the limitation of the included studies, imprecision, inconsistency across the studies' results, and suspicion of publication bias. None of the included studies reported adverse perinatal outcomes or congenital malformations.
  
  
  CONCLUSIONS
  There is evidence that adding GnRH agonist during the luteal phase improves the likelihood of ongoing pregnancy. However, this evidence is of very low quality and there is no evidence for adverse perinatal outcome and congenital malformations. We therefore believe that including this intervention in clinical practice would be premature.
authors: Department of Obstetrics and Gynecology, Ribeirao Preto Medical School, University of Sao Paulo (DGO-FMRP-USP), Ribeirao Preto, Brazil.
authors: W P
authors: WP
authors: Martins
authors: Department of Obstetrics and Gynecology, Ribeirao Preto Medical School, University of Sao Paulo (DGO-FMRP-USP), Ribeirao Preto, Brazil.
authors: R A
authors: RA
authors: Ferriani
authors: Department of Obstetrics and Gynecology, Ribeirao Preto Medical School, University of Sao Paulo (DGO-FMRP-USP), Ribeirao Preto, Brazil.
authors: P A
authors: PA
authors: Navarro
authors: Department of Obstetrics and Gynecology, Ribeirao Preto Medical School, University of Sao Paulo (DGO-FMRP-USP), Ribeirao Preto, Brazil.
authors: C O
authors: CO
authors: Nastri
mesh_terms: D000022:Abortion, Spontaneous; D000328:Adult; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists*; D006728:Hormones / Q000008:administration & dosage*; D006801:Humans; D050498:Live Birth; D008183:Luteal Phase / Q000187:drug effects*; D010062:Ovulation Induction / Q000379:methods; D011247:Pregnancy; D018873:Pregnancy Rate; D016032:Randomized Controlled Trials as Topic; D027724:Reproductive Techniques, Assisted / Q000706:statistics & numerical data*; D012306:Risk
chemical_list: D006728:Hormones; D007987:Gonadotropin-Releasing Hormone
keywords: ICSI; IVF; assisted reproduction; infertility; luteal phase support; subfertility