Abstract:Objective To compare the difference of cumulative delivery rate of three commonly used ovulation induction programs per oocyte retrieval cycle,in order to guide clinical application.Methods The clinical data of 1 562 infertile patients with normal ovarian response who received in vitro fertilization embryo transfer (IVF-ET) from July 2017 to May 2018 were retrospectively analyzed.Among them,514 cases were treated with mid-luteal-phase long GnRH agonist protocol (group A),531 cases were treated with early-follicular-phase long GnRH agonist protocol (group B) and 531 cases were treated with GnRH antagonist protocol(group C).The outcome of the study was no transplantable embryo or first live birth.The follow-up period was 2 years.The clinical outcomes and cumulative delivery rate of the three groups were compared.Each group was divided into four subgroups according to age:20-30 years old,31-35 years old,36-40 years old,and over 40 years old.The cumulative delivery rate,miscarriage rate and twin rate of the same group in different age subgroups and the same age subgroup in different groups were compared.Results There was no significant difference in basal hormone level,oocyte number,oocyte maturation rate,fertilization rate,abortion rate,twin rate and cumulative delivery rate among the three groups (P>0.05).The high-quality embryo rate of group B was significantly higher than that of group A and C,and the implantation rate was significantly higher than that of group A (P<0.017).The dosage of gonadotropin(Gn),and the level of estradiol(E2) and progesterone on human chorionic gonadotropin injection day(HCG day) in group A and B were higher than those in group C,and the level of luteinizing hormone (LH) on HCG day was lower than that in group C (P<0.05).Compared with the patients of different ages in the same group,with the increase of age,the cumulative delivery rate decreased (P<0.01),and the abortion rate increased (P<0.01).Compared with the patients of different groups in the same age group,the cumulative delivery rate of group C (71.31%) in 36-40 years old group was higher than that of group A (53.23%),group B (53.54%) (P<0.017).There was no significant difference in cumulative delivery rate,twin rate and abortion rate among other age groups (P>0.05). Conclusion For infertile patients aged from 36 to 40 years old,it is possible to obtain better clinical outcomes by choosing GnRH antagonist scheme than mid-luteal-phase long GnRH agonist scheme and early-follicular-phase long GnRH agonist scheme,but there is no obvious difference in other age groups,so individualized selection under the three schemes is feasible.