To investigate the effects of oocyte maturation trigger using follicle-stimulating hormone (FSH) plus human chorionic gonadotropin (hCG) on clinical outcomes of in vitro fertilization/intracytoplasmic sperm injection and embryo transfer (IVF/ICSI-ET) in gonadotropin-releasing hormone agonist (GnRH-a) cycles.

The retrospective cohort study included 682 patients aged up to 40 years with normal ovarian response who underwent IVF/ICSI-ET at Department of Reproductive Medicine, Women and Children's Hospital, Xiamen University School of Medicine between Feburary 2016 and April 2017. Patients were grouped by whether oocyte maturation was triggered with 250 μg recombinant hCG (r-hCG) plus 300 U urinary FSH (uFSH, dual trigger group, n=439) or 250 μg r-hCG alone (r-hCG group, n=243). The main observation indexes were the clinical pregnancy rate and the live birth rate, and the secondary observation indexes were the high-quality embryo rate, the implantation rate, the biochemical pregnancy rate, the abortion rate, etc.

There were no statistically significant differences between the two groups in age, infertility duration, body mass index (BMI), anti-Müllerian hormone (AMH), total dosage and duration of gonadotropin (Gn) used, number of embryos transferred (all P>0.05). The live birth rate, the clinical pregnancy rate, the miscarriage rate, the normal fertilization rate, the cleavage rate, the embryo formation rate and the high-quality embryo rate were not significantly different between the two groups (all P>0.05). The implantation rate [40.47% (191/472)] and the biochemical pregnancy rate [64.20% (156/243)] were higher in dual trigger group than in r-hCG group [32.42% (272/893), P=0.003; 55.35% (272/893), P=0.025].

Dual trigger of oocyte maturation with 250 μg r-hCG plus 300 U uFSH has no benefit on the clinical pregnancy rate and the live birth rate, but could improve the implantation rate and the biochemical pregnancy rate in women undergoing short-acting GnRH-a protocol in IVF/ICSI-ET.

Fertilization in vitro; Follicle-stimulating hormone; Dual trigger; Recombination human chorionic gonadotropin trigger; Embryo transfer