Comparative Effectiveness of Follitropin Delta, Follitropin Alpha, and hMG in ART Cycles: A Single-Center Retrospective Cohort Study With Propensity Score Matching.

Objective: To compare clinical outcomes of ART cycles stimulated with follitropin delta, follitropin alpha, or human menopausal gonadotropin (hMG) using a single-center retrospective cohort with propensity score matching (PSM). Methods: We analyzed 20 809 ART cycles (2021-2024). PSM adjusted for age, body weight, anti-Müllerian hormone, antral follicle count, prior ART attempts, stimulation protocol, and trigger method. The matched cohort comprised 7,647 cycles (2549/group). The primary outcome was oocyte yield. Secondary outcomes included blastocyst development, ovarian enlargement ≥ 5 cm, and clinical pregnancy rates. Results: The primary outcome regarding oocyte yield was statistically indeterminate across different analytical approaches, and the observed differences were clinically marginal. Both recombinant FSH preparations showed higher blastocyst yields and a lower observed incidence of ovarian enlargement ≥ 5 cm compared with hMG; the latter finding, however, does not establish a clinical safety advantage because clinically diagnosed OHSS was not evaluated. Clinical pregnancy rates were comparable among the three groups. Conclusions: Differences in oocyte yield among follitropin delta, follitropin alpha, and hMG were small and statistically inconsistent. Secondary findings should be interpreted as exploratory, suggesting broadly comparable clinical performance among the three gonadotropin preparations.