Impact of Basal Luteinizing Hormone Levels on IVF Outcomes in PCOS: Clinical Insights

Elevated basal LH in women with PCOS preserves metaphase II oocyte yield and embryo quality during IVF/ICSI but amplifies ovarian responsiveness and OHSS risk — making basal LH a useful pre-cycle risk signal to guide stimulation protocol choice and mitigation planning.

This single-center retrospective cohort reviewed 1,269 women with PCOS treated from 2013–2023 under flexible GnRH-antagonist or long GnRH-agonist protocols. Predefined primary endpoints included metaphase II (MII) oocyte yield, embryo-quality metrics, and OHSS incidence. The study’s design and limited prospective follow-up support internal validity for the sampled population while constraining external generalizability.

Higher basal LH did not reduce MII yield or impair embryo quality: MII counts, fertilization rates, and numbers of high-quality embryos were comparable across groups. At the same time, elevated LH correlated with greater oocyte retrieval and higher OHSS rates, signaling increased ovarian responsiveness and a clear safety consideration despite preserved embryo competence.

Compared with long-agonist protocols, GnRH-antagonist cycles shortened stimulation, required lower recombinant FSH doses, and in the elevated-LH subgroup were associated with higher proportions of oocytes, MII oocytes, and high-quality embryos. These data favor preferential use of antagonist protocols for efficiency and risk management in patients with higher basal LH rather than a universal protocol change.

Basal LH can be incorporated into pre-cycle endocrine evaluation to help stratify OHSS risk and individualize stimulation intensity and trigger planning. Practical mitigation options supported by the findings include choosing a GnRH-antagonist protocol, considering alternative trigger strategies, and planning elective vitrification/freeze-all pathways to avoid fresh-transfer OHSS exposure. Basal LH should be viewed as one of several endocrine predictors to inform pre-cycle planning.

Key Takeaways:

• Elevated basal LH in PCOS preserves MII oocyte yield and embryo quality while increasing ovarian response and OHSS risk.
• Women with PCOS—particularly those with higher basal LH—are the subgroup most directly impacted by these findings.
• Incorporate basal LH into pre-cycle assessment to guide choice of antagonist protocols and trigger/freeze-all risk-mitigation pathways.