Personalizing LH supplementation in female infertility: which patients may benefit

Peter Humaidan answers a practical question: which women in ART programmes truly need LH supplementation, and which do not. The answer cannot be reduced to a single lab value.

The first thesis: there is no single threshold for "low" serum LH. Moreover, the blood LH level does not equal the bioactivity of the molecule or receptor sensitivity — so relying on the lab value alone is wrong.

Humaidan identifies four proven groups that benefit from adding LH: hypogonadotropic hypogonadism; deep LH suppression under GnRH antagonists; POSEIDON 1–4 poor responders; and carriers of FSHR/LHR polymorphisms and the β-LH variant.

The POSEIDON concept (Patient-Oriented Strategies Encompassing Individualized Oocyte Number) frames the personalisation of stimulation in patients with a poor or suboptimal response — it is in these groups that LH support matters most.

A separate emphasis is genetics. FSH-receptor polymorphisms occur in roughly 20% of patients; the β-LH variant is a frequent but under-diagnosed cause of a "strange" response to a standard protocol.

Hence a specific strategy: for a suspected FSHR polymorphism — a higher FSH dose; for the β-LH variant — adding LH activity (hCG or recombinant LH). Different mechanisms call for different decisions.

In practice this means moving from "one dose for all" to choosing the form and the very presence of LH support according to age, ovarian reserve, the suppression protocol and the patient's genetic background.

Hypogonadotropic hypogonadism is the extreme case where follicles do not grow at all without exogenous LH; deep suppression under antagonists is a reversible but clinically meaningful mid-stimulation LH dip that is reasonable to compensate.