Gonadotropin releasing hormone agonist and standard dosage of human chorionic gonadotropin trigger improve the in vitro fertilization and embryo transfer/intracytoplasmic sperm injection treatment prognosis of patients with history of poor fertilization outcomes

Objective To investigate whether combined trigger [gonadotropin releasing hormone (GnRH) agonist (GnRH-a) combined with standard dosage human chorionic gonadotropin (hCG) trigger] in GnRH antagonist protocol could improve the treatment outcomes of patients with history of poor fertilization outcomes (low fertilization rate or no valuable embryo due to poor oocyte quality). Methods This was a retrospective self-controlled study. The study period was between Jan. 1st 2014 and Dec. 31st 2015. All patients were accepted GnRH antagonist flexible protocol and GnRH-a and standard dosage of hCG trigger with hisory of poor fertilization outcomes followed standard hCG trigger. The relative data were analyzed. Results The age was (31.8±3.9) (range from 20 to 40) years old, 78.9% of them were primary infertility. Compared with hCG trigger group, the initial dosage of gonadotropin (Gn) used was significantly higher in combined trigger group [(258.4±93.7) IU vs. (215.0±90.7) IU, P=0.001] and the duration of Gn used stimulation was significantly shorter in combined trigger group [(10±1) d vs. (12±3) d, P<0.001). The total dosage of Gn used was significantly lower in combined trigger group [(2 472.0±913.6) IU vs. (2 846.8±1 243.2) IU, P=0.001]. The number of oocyte pick up and fertilization rate were significantly higher in combined trigger group (14±9 vs. 12±6, 54.6% vs. 38.1%, respectively, P=0.022, P<0.001). The rate of MII oocyte was comparable between the two groups. The 2 pronucleus (PN) oocyte rate was significantly higher in combined group (45.8% vs. 25.3%, P<0.001). The clinical pregnancy rate, the implantation rate and the live birth rate were significantly higher in combined trigger group (44.6% vs. 2.5%, 29.4% vs. 1.4%, 35.7% vs. 0, respectively, all P<0.001). Conclusion The GnRH antagonist protocol with GnRH-a and standard dosage of hCG trigger significantly improve the live birth rate of patients with history of low fertilization rate or no valuable embryo due to poor oocyte quality. Key words: Gonadotropin releasing hormone antagonist protocol; Controlled ovarian stimulation; Gonadotropin releasing hormone agonist trigger; Combined trigger