Recombinant LH supplementation during PPOS in diminished ovarian reserve: a propensity score-matched analysis

Purpose To determine whether recombinant luteinizing hormone (rLH) supplementation improves oocyte yield in women with diminished ovarian reserve (DOR) undergoing progestin-primed ovarian stimulation (PPOS), and to evaluate its associations with stimulation and embryological outcomes. Methods This retrospective cohort study included women with DOR undergoing IVF/ICSI with PPOS between January 2018 and January 2026 at two affiliated tertiary fertility centers. Among 6793 screened PPOS cycles, 1051 eligible cycles were identified: 164 received recombinant FSH (rFSH) alone and 887 received rFSH plus 75 IU/day rLH. Propensity score matching (1:1) based on female age, BMI, and total AFC yielded 121 women per group. The primary outcome was the number of oocytes retrieved. Multivariable negative binomial regression was used to assess the independent association between rLH supplementation and oocyte yield. Results After matching, the number of retrieved oocytes did not differ significantly between the rFSH+rLH and rFSH-only groups (3 [2–5] vs 3 [2–6]; p=0.166). No significant differences were observed in MII oocytes (3 [1–4] vs 3 [2–5]; p=0.184), 2PN oocytes (2 [1–4] vs 2 [1–4]; p=0.493), maturation rate (88.19% [66.67–100] vs 100% [66.67–100]; p=0.686), or fertilization rate (100% [71.43–100] vs 100% [60–100]; p=0.204). In the primary multivariable negative binomial regression model, rLH supplementation was not significantly associated with oocyte yield (adjusted IRR 0.885, 95% CI 0.764–1.025; p=0.103). Higher AFC was independently associated with greater oocyte yield (adjusted IRR 1.164, 95% CI 1.123–1.205; p<0.001), whereas increasing female age was associated with lower oocyte yield (adjusted IRR 0.986, 95% CI 0.974–0.999; p=0.036). Conclusion Recombinant LH supplementation was not associated with higher total or mature oocyte yield in women with diminished ovarian reserve undergoing progestin-primed ovarian stimulation. The association remained non-significant after adjustment for key pretreatment predictors of ovarian response and in a sensitivity analysis additionally adjusting for cumulative rFSH exposure.