Background: General concern is that the pregnancy rate is higher with
GnRH-agonist as a protocol of pituitary suppression. GnRH-antagonist
protocol provides a shorter period of administration and an easy
flexible protocol. Objective: In this study, the outcomes of GnRH
agonist and antagonist in ICSI cycles are compared in normo responder
patients. Materials and Methods: In this randomized clinical trial, 300
normoresponders undergoing ICSI were randomly divided to GnRh agonist
(n=150) and GnRh antagonist (n=150) groups. The main outcome
measurements were chemical, clinical and ongoing pregnancy rates (PR).
Results: The mean duration of stimulation were 9.6±1.6 and
8.2±1.6 days in agonist and antagonist groups respectively
(p=0.001). The mean number of MII oocyte retrieved in agonist and
antagonist groups were 7.7±4.0 and 6.9±4.3 respectively
(p=0.03). There was no significant difference between two groups
regarding mean number of gonadotrophin ampoules, follicles, occytes,
total embryos and good quality embryos, OHSS incidence, and abortion
rate. Chemical pregnancy rate was 35.3% in agonist and 39.3% in
antagonist group. Clinical pregnancy rate was 35.3% in agonist and 34%
in antagonist group. Ongoing pregnancy rate was 45 (31.3%) in agonist
and 44 (29.3%) in antagonist group. There was no significant difference
between two groups in pregnancy rates. Conclusion: In this study
antagonist protocol was shown to be an easy, safe and friendly protocol
in Iranian normoresponder patients, having similar outcomes with
standard agonist protocol but shorter period of stimulation
