Dual triggering fails to improve mature oocyte yield in poor responders: a cycle-based analysis in POSEIDON group 4...

Poor ovarian responders (PORs) represent a challenging population in assisted reproductive technology, where even small increases in oocyte yield may meaningfully impact reproductive outcomes. Final oocyte maturation triggering is a critical step in controlled ovarian stimulation. While human chorionic gonadotropin (hCG) has traditionally been used alone, dual triggering-combining hCG with a gonadotropin-releasing hormone agonist (GnRHa)-has emerged as a strategy to enhance oocyte yield and maturation. However, evidence in PORs remains limited and inconsistent, likely reflecting the heterogeneity of the populations studied. Within the POSEIDON classification, group 4 patients-older women with reduced ovarian reserve-represent a relevant target for optimized stimulation strategies.

This retrospective cohort study included GnRH antagonist IVF cycles in POSEIDON group 4 women (age ≥35 years with AFC <5 and/or AMH <1.2 ng/mL). Final oocyte maturation was triggered with recombinant hCG alone or dual trigger (GnRHa + hCG). The primary outcome was the number of mature (MII) oocytes per cycle. Secondary outcomes included total oocytes retrieved, fertilization rate, embryo utilization, and clinical outcomes. Analyses were performed using generalized estimating equations (GEE) to account for repeated cycles.

A total of 1,824 cycles were included (354 dual trigger, 1,470 hCG alone). No significant differences were observed in mature oocytes, maturation rate, or total oocytes retrieved between groups. Fertilization rate was slightly higher with dual trigger (74.1% vs. 69.9%; p = 0.04), whereas embryo utilization was lower (62.4% vs. 70.4%; p < 0.001). Clinical pregnancy and live birth rates were similar. In multivariable analysis, dual triggering was not associated with mature oocyte yield, while age and AMH remained significant predictors (p < 0.001).

Dual triggering does not improve mature oocyte yield or clinical outcomes in POSEIDON group 4 patients, supporting no clear benefit for its routine use in this population.