Luteinizing Hormone (LH)
Luteinizing hormone is produced by the anterior pituitary gland. It drives two essential reproductive events: the mid-cycle LH surge, which triggers ovulation, and ongoing stimulation of the corpus luteum to produce progesterone after ovulation.
The LH surge is the signal that ovulation is imminent. Most urinary LH tests detect this surge 24 to 36 hours before follicle rupture. Timing intercourse or insemination to the surge is the basis of most ovulation-detection approaches. But surge detection is not the same as confirmed ovulation. In LUF syndrome, the surge occurs normally while the follicle fails to rupture.
Baseline LH levels on cycle day 2 or 3 are part of an RRM hormonal panel. An elevated LH-to-FSH ratio is one finding consistent with PCOS. Persistently elevated LH outside the expected surge window can reflect hypothalamic disruption, stress, or thyroid dysfunction.
LH is also used therapeutically in RRM practice. Cycle-timed hCG injections, which mimic the action of LH, can support corpus luteum function and assist with follicle release in cases where the endogenous surge is insufficient. This is a targeted, restorative intervention, not suppression.
Without cycle chart data anchoring the timing, LH values lose much of their interpretive value. A single LH drawn without knowing where the patient is in her cycle is close to meaningless. Chart-based medicine avoids this problem.
This content is for educational purposes only and does not constitute medical advice. Consult an RRM clinician or healthcare provider for guidance specific to your situation.