IVF/ICSI treatment for patients with diminished ovarian reserve with or without Kuntai capsule pretreatment: a retrospective cohort study stratified by a controlled ovarian stimulation regimen.

Background: Kuntai capsules, a traditional Chinese medicine, are speculated to improve the treatment outcomes of patients with ovarian reserve dysfunction (DOR), but existing evidence is limited.

Objective: To investigate the effects of Kuntai capsule pretreatment on the IVF/ICSI treatment outcomes of DOR patients with different ovarian stimulation regimens (PPOS, antagonists, and microstimulation).

Method: A retrospective cohort study design was used to include 7271 DOR patients who underwent IVF/ICSI between January 2015 and February 2025. After baseline data were balanced through propensity score matching (PSM), 1474 patients were ultimately included. The number of retrieved eggs, laboratory indicators, and clinical outcomes were compared between the group pretreated with Kuntai capsules and the group not pretreated with Kuntai capsules under three ovarian stimulation regimens, and confounding factors were controlled via a generalized estimating equation (GEE) model.

Result: In the PPOS regimen, the number of retrieved eggs (without kuntai: 2.00 [1.00;4.00], with kuntai: 2.00 [1.00;3.00], p<0.001) and normal fertilized eggs (without kuntai:2.00 [1.00;3.00], with kuntai: 2.00 [1.00;2.00], p=0.004) in the Kuntai pretreatment group significantly decreased, but the embryo utilization rate increased (without kuntai:101 (69.2%), with kuntai: 79 (74.5%), p=0.012). There was no difference between the two groups in the antagonist regimen. The Kuntai group had a higher failure rate for egg retrieval in the microstimulation program (without kuntai: 0 (0.00%), with kuntai:6 (6.25%), p=0.029). Among the three regimens, Kuntai pretreatment did not significantly improve the clinical pregnancy rate, live birth rate, or other outcomes (all p>0.05). Age stratification analysis and GEE analysis did not reveal significant differences.

Conclusion: Pretreatment with Kuntai capsules did not significantly improve the number of retrieved eggs or clinical pregnancy outcomes in DOR patients under different ovarian stimulation regimens, and its application effect is limited. Further verification through prospective research is needed in the future.