Among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth dependent on the type of analogue used? A systematic review and meta-analysis

This systematic review and meta-analysis aimed to answer the following clinical question: among patients treated for IVF with gonadotrophins and GnRH analogues, is the probability of live birth per randomized patient dependent on the type of analogue used? Eligible studies were randomized controlled trials (RCTs), published as a full manuscript in a peer-reviewed journal, that contained sufficient information to allow ascertainment of whether randomization was true and whether equality was present between the groups compared. A literature search identified 22 RCTs comparing GnRH antagonists and GnRH agonists that involved 3176 subjects. Where live birth was not reported in a study that fulfilled the inclusion criteria, an effort was made to contact the corresponding authors to retrieve the missing information. If this was not possible, the reported outcome measure, clinical pregnancy or ongoing pregnancy was converted to live birth in 12 studies using published data (Arce et al., 2005). No significant difference was present in the probability of live birth between the two GnRH analogues [odds ratio (OR), 0.86; 95% confidence intervals (CI), 0.72 to 1.02]. This result remains stable in subgroup analysis that ordered the studies by type of population studied, gonadotrophin type used for stimulation, type of agonist protocol used, type of agonist used, type of antagonist protocol used, type of antagonist used, presence of allocation concealment, presence of co-intervention and the way the information on live birth was retrieved. In conclusion, the probability of live birth after ovarian stimulation for IVF does not depend on the type of analogue used for pituitary suppression.