Characteristics of antagonist protocol in fresh ET cycles and effect on pregnancy outcomes
Antagonist could produce a rapid suppression on pituitary function, which could decrease gonadotropin dosage and risk of ovarian hyperstimulation syndrome. Compared with ultra-long and long protocols, AFC in antagonist protocol was lower in our study. However, number of retrieved oocytes and 2PN zygotes had no statistical significance. The analysis of pregnancy outcomes showed that compare with ultra-long and long protocols, IR, CPR and LBR in antagonist protocol were poorer, however, strict P adjustment of Bonferroni method (Padj=0.008) in pairwise under multiple comparisons made the statistical difference difficult to achieve. The rates of BPR, MR, early MR and late MR were similar among ultra-long, long and antagonist protocols. Thalluri V. reported CPR in antagonist protocol was 23.6% in patients with adenomyosis, which was similar to our data and significantly lower than the reported CPR in ultra-long or long protocols(6-8, 15). Kolanska K compared pregnancy outcomes of GnRH-agonist versus GnRH-antagonist protocols in women with endometriosis-associated infertility and inferred GnRH-antagonist associated dysfunction of endometrial receptivity might result in decreased CPR and LBR (16).