To investigate the effect of Kuntai Capsule（坤泰胶囊）pretreatment combined with different cryopreservation carriers on embryo transfer outcomes in patients with diminished ovarian reserve（DOR）.

A retrospective analysis was conducted on 120 DOR patients undergoing in vitro fertilization（IVF）-frozen embryo transfer（FET）at the Reproductive Medicine Center of Huizhou Central People’s Hospital from January 2021 to October 2023. The patients were divided into four groups based on intervention：Group A［n＝30，conventional vitrification carrier（Cryotop）without herbal pretreatment］，Group B（n＝30，cryotop with Kuntai Capsule pretreatment），Group C［n＝30，novel tubular cryopreservation carrier（Tube Cryodevice Tiny-B1）without herbal pretreatment］，Group D（n＝30，Tiny-B1 with Kuntai Capsule pretreatment）. Groups B and D received Kuntai Capsule for three menstrual cycles. The parameters including anti Mullerian hormone（AMH），estradiol（E2），serum follicle stimulating hormone（FSH），endometrial thickness（ET），total antral follicle count，oocytes retrieved，high-quality embryos，embryo survival rate，implantation rate，clinical pregnancy rate，biochemical pregnancy rate and maternal-neonatal outcomes were compared. The data was analyzed using SPSS26.0.

Baseline characteristics showed no significant differences among four groups（P>0.05）. After intervention，AMH level in Group D was significantly lower than those in Groups B and C（P＝0.012）；the E2 levels in Groups Cand D were higher than those in Groups A and B（P＝0.025）；the endometrial thickness in Group D exceeded that in the other groups（P<0.000 1）. Total antral follicles：the result of Group D was higher than that of Group A（35.7%，P＝0.003）and that of Group C（31.7%，P＝0.009）. Oocytes retrieved：the result of Group D surpassed that of Group A（P＝0.021）but showed no significant difference compared with that of Group B（P＝0.081）. High-quality embryos：the result of Group B increased by 34.2% compared with that of Group A（P＝0.016），while the result of Group D increased by 51.0% compared with that of Group C（P＝0.028）. Embryo survival rates showed no statistical difference（P>0.05），but implantation rates in Groups B and D were significantly higher than those in Groups A and C（P<0.05）. Clinical pregnancy rates in Groups B（70.00%）and D（73.33%）were significantly higher than those in Group A（50.00%）and Group C（53.33%）（P<0.05）. No differences in biochemical pregnancy rates were observed（P>0.05）. Live birth rates in Group D were markedly elevated compared with those in Group A（RR＝1.67，95% CI［1.12，2.47］，P＝0.004）. The live birth rates of Group B also improved compared with that of Group A（RR＝1.50，95% CI［1.02，2.21］，P＝0.021）. Neonatal preterm birth rates and birth weights showed no differences among four groups（P>0.05）.

Kuntai Capsule pretreatment improves ovarian function and endometrial receptivity in DORpatients，enhancing implantation and clinical pregnancy rates. Combined with the novel tubular cryopreservation carrier，Kuntai Capsule further increases oocyte yield，high-quality embryos and live birth rates.