Ultra-low-dose and very-low-dose Lupron downregulation protocols for poor responders based on POSEIDON group 3 and 4 classifications.

Purpose: The objective of this study was to assess if very-low-dose Lupron (VLDL) and ultra-low-dose Lupron (ULDL) protocols can have comparable cycle outcomes when compared to other "poor responder" stimulation protocols based on POSEIDON classification groups 3 (PG3) and 4 (PG4).

Methods: A retrospective cohort study at a single, large academic center was performed. Women in PG3 (age < 35, AMH < 1.2 ng/mL) or PG4 (age ≥ 35, AMH < 1.2 ng/mL) undergoing in vitro fertilization using an ULDL (Lupron 0.1 to 0.05 mg daily), VLDL (Lupron 0.2 to 0.1 mg daily), microflare (Lupron 0.05 mg twice a day), estradiol priming/antagonist, antagonist, or minimal stimulation protocols from 2012 to 2021 were included. The primary outcome was the number of mature oocytes (MII) obtained. The secondary outcome was live birth rate (LBR).

Results: The cohort included 3601 cycles. The mean age was 38.1 ± 3.8 years. In the PG3 group, ULDL and VLDL protocols produced a comparable number of MIIs (5.8 ± 4.3 and 5.9 ± 5.4, respectively) and live births (33.3% and 33.3%, respectively) when compared to other protocols. In the PG4 group, ULDL and VLDL protocols resulted in a higher percentage of MIIs when compared to microflare or minimal stimulation (Microflare/ULDL: adjusted relative risk (aRR) 0.78 (95% CI 0.65, 0.95); min stim/ULDL: aRR 0.47 (95% CI 0.38, 0.58); microflare/VLDL: aRR 0.77 (95% CI 0.63, 0.95); min stim/VLDL: aRR 0.47 (95% CI 0.38, 0.95)). There were no significant differences in LBR.

Conclusion: Dilute Lupron downregulation protocols have comparable outcomes to other poor responder protocols and are reasonable to use.