Abstract

Background: Subfertility is one of major problems worldwide, which led to continuous researches and advancements in the field of assisted reproductive technology. Both agonist and antagonist protocols are clinically used, hence comparison of both protocols is essential for clinical evaluation of their outcomes.

Aim: To compare of the outcomes of GnRH short agonist and GnRH antagonist protocols in normo-responder patients undergoing intracytoplasmic sperm injection ICSI.

Method: A prospective clinical trial conducted at Najaf Fertility Centre, during the period from 1st of March 2016 to 1st of February 2018. This trial Included 394 subfertility women aged less than 38 years, after obtaining of oral and written consent. All patients underwent intracytoplasmic sperm injection due to male factor except azoospermia, certain female factors, unexplained subfertility and mixed type to be assigned to short GnRH agonist protocol or GnRH antagonist protocol. The main outcomes measures were duration of stimulation days, numbers of 75 IU gonadotrophin ampules, estradiol levels on day of hCG, embryological parameters, fertilization rate, cleavage rate, chemical pregnancy rate and clinical pregnancy rate per cycle and per embryo transfer, multiple gestation, early pregnancy loss, and ovarian hyper stimulation syndrome, first trimester abortion.

Results: Out of the study sample, 19 patients were cancelled due to various reasons, and the remaining 375 subfertile women continued the ICSI cycles. Stimulation days and total numbers of gonadotrophins was significantly higher in GnRH-agonist protocol group, than GnRH-antagonist (10.13 vs 9.41and 28 vs 21, respectively, (P<0.05). Frequency of ovarian hyper stimulation syndrome was significantly higher in agonist than antagonist group 17.1% and 9.4%, respectively. No statistically significant differences had been found between both groups in all embryological data (P>0.05) except the mean number of good quality embryos it was significantly higher in agonist than antagonist group, 3.32and 3.02, respectively. The agonist group had significantly higher fertilization rate, Positive β-hCG, clinical pregnancy per cycle and clinical pregnancy per embryo transfer than antagonist group, in all comparisons, (P<0.05), no statistically significant difference found in cleavage rate, chemical pregnancy/cycle, multiple gestation or first trimester abortion, (P>0.05).

Conclusion: Shorter duration of stimulation days, fewer numbers of gonadotrophin injections and lower incidence of OHSS in GnRH-antagonist make the GnRH-antagonist more patient friendly protocol in ART. However, significant higher fertilization rate, good quality embryo and clinical pregnancy rate in agonist short protocol tips the balance in favor of the short protocol.

Keywords: ICSI, antagonist, normoresponding.