GnRH agonist; GnRH antagonist; HCG; OHSS
Final oocyte maturation in GnRH antagonist co-treated IVF/ICSI cycles can be triggered with HCG or a GnRH agonist. We conducted a systematic review and meta-analysis of randomized controlled trials to evaluate the efficacy and safety of the final oocyte maturation trigger in GnRH antagonist co-treated cycles. Outcome measures were ongoing pregnancy rate (OPR) and ovarian hyperstimulation syndrome (OHSS) incidence. Searches: were conducted in MEDLINE, EMBASE, Science Direct, Cochrane Library, and databases of abstracts. There was a statistically significant difference against the GnRH agonist for OPR in fresh autologous cycles (n = 1024) with an odd ratio (OR) of 0.69 (95% CI: 0.52-0.93). In oocyte-donor cycles (n = 342) there was no evidence of a difference (OR: 0.91; 95% CI: 0.59-1.40). There was a statistically significant difference in favour of GnRH agonist regarding the incidence of OHSS in fresh autologous cycles (OR: 0.06; 95% CI: 0.01-0.33) and donor cycles respectively (OR: 0.06; 95% CI: 0.01-0.27). In conclusion GnRH agonist trigger for final oocyte maturation trigger in GnRH antagonist cycles is safer but less efficient than HCG.