GnRH agonist and GnRH antagonist in intracytoplasmic injection cycles

The long agonistic protocol for controlled ovarian hyperstimulation (COH) is effective and used most often, thus is considered the gold standard. Therefore any new regimen has to be compared in its results with those obtained with the long protocol. This report compares the efficacy of GnRH agonist and antagonist in a retrospective study of IVF/ICSI carried out in a tertiary teaching hospital from 2003 to 2006. Only the first COH cycle followed by IVF-ICSI from 200 couples (agonist = 120 and antagonist = 80) were analysed. The end points studied included the number of oocytes recovered, number of mature (MII) oocytes, fertilization, cleavage, morphology based embryo quality, pregnancy rate, quantity and cost of gonadotrophin. The average age of female subjects was 35.1 +/- 4.7 years with 50% being 35 years and above. Major infertility factors were tubal blockage, male factor and endometriosis altogether comprising 68%. GnRH agonist and antagonist cycle parameters were comparable except lesser amount of gonadotrophin was used with lower resultant costs (both p < 0.0005) in antagonistic regime. Antagonist regime produce somewhat more good quality embryos (p = 0.065), an insignificant difference. A clinical pregnancy rate per embryo transfer of 16.3% in agonist and 20.6% in antagonist regime was achieved respectively. In conclusion, GnRH antagonist protocol produced a COH response, embryonic development and pregnancy rates on par to GnRH agonist regime. Moreover GnRH antagonist protocol required a shorter stimulation period plus fewer complications. Hence GnRH antagonist regime provided means for a friendlier, convenient and cost effective protocol for patients.