Abstract:

Objective  To investigate the clinical effect of dual trigger with gonadotropin-releasing hormone agonist (GnRHa) and low-dose human chorionic gonadotropin (hCG) on oocyte maturation for normal responders. Methods  Complete clinical data of 270 in vitro fertilization and embryo transfer（IVF-ET）cycles from normal responder patients with a GnRH antagonist-based ovarian stimulation protocol who were transferred with fresh embryos were retrospectively analyzed. The patients were divided into three groups based on trigger protocols: hCG group, GnRHa and low-dose hCG group，GnRHa group. The retrieved oocytes, clinical pregnancy rates, implantation and ovarian hyperstimulation syndrome (OHSS) were compared. Results  The retrieved oocytes in GnRHa and low-dose hCG group significantly increased compared with the other two groups even though the number of large follicles on trigger day were similar. Clinical pregnancy rates of hCG group, GnRHa and low-dose hCG group and GnRHa group were 41.72%, 59.49% and 40.00%, respectively, which were significantly different（all P<0.05）. The implantation rates of hCG group, GnRHa and low-dose hCG group and GnRHa group were 23.53%, 35.43% and 23.40%, respectively, which were also significantly different（all P<0.05）. The miscarriage rates among the three groups were similar（P>0.05）. Only one woman with pregnancy in hCG group developed mild OHSS. Conclusion  Dual trigger of oocyte maturation with GnRHa and low-dose hCG in normal responders can increase retrieved oocytes and  improve implantation rate and pregnancy rate.

Key words: Gonadotropin-releasing hormone antagonist, Human chorionic gonadotropin, Gonadotropin-releasing hormone agonist, Ovulation trigger, Pregnancy rate