Objective:

To compare the cumulative live birth rate (CLBR) associated with ovarian stimulation using recombinant follicle stimulating hormone (rFSH) alone or in combination with recombinant LH (rLH) or human menopausal gonadotropin (HMG), with a focus on the primary outcome measure.

Key Findings:

• The rFSH+HMG group required significantly higher total gonadotropin doses and longer stimulation duration than both the rFSH+rLH and rFSH groups (P < 0.001), indicating a less efficient stimulation protocol.
• The rFSH+rLH group exhibited a higher number of follicles ≥14 mm on trigger day compared to the rFSH+HMG group (P < 0.05), suggesting better follicular response.
• The rFSH+rLH group showed a higher CLBR compared to the rFSH group (61.31% vs. 51.48%, P = 0.036), highlighting the potential benefit of LH supplementation.
• In multivariable Fine–Gray models, rFSH+rLH was associated with a higher probability of cumulative live birth compared to rFSH alone (adjusted sHR 1.29, P = 0.020) and rFSH+HMG (adjusted sHR 1.23, P = 0.039).

Interpretation:

Recombinant LH supplementation was associated with a higher CLBR compared to rFSH alone or rFSH combined with HMG, although the difference versus rFSH+HMG was not statistically significant in unadjusted analyses, indicating a need for careful interpretation in clinical practice.

Limitations:

• The study is retrospective and may be subject to biases inherent in such designs, including selection bias and confounding factors.
• Causality cannot be inferred from the findings, and further prospective studies are needed to validate these results.

Conclusion:

These findings suggest a potential benefit of rLH supplementation in ART for older women, but results should be interpreted with caution, and further research is warranted to confirm these outcomes.