Luteinizing Hormone (LH)
Luteinizing hormone is an anterior pituitary glycoprotein that stimulates testicular Leydig cells to produce testosterone in men and triggers ovulation and corpus luteum progesterone synthesis in women.
Standard vs. Optimal Reference RangesmIU/mL
Standard reference intervals represent the statistical 95% distribution of unselected commercial populations. Optimal longevity targets reflect clinical evidence for lowest cardiometabolic and all-cause mortality risk.
Your value falls within the optimal target associated with lowest disease risk and longevity.
1.7 - 8.6 mIU/mL (Male), Phase-dependent (Female)
General reference distribution across unselected commercial populations.
2.0 - 6.0 mIU/mL (Male)
Concentration target associated with minimal all-cause cardiometabolic mortality.
Molecular Mechanism & Clinical Purpose
Secreted in pulses in response to hypothalamic GnRH. Binds LHCGR receptors on Leydig/theca cells, activating cyclic AMP signaling to promote STAR protein expression and cholesterol entry into mitochondria.
Differential Diagnosis
Elevated Levels (LH High)
- •Primary hypogonadism (Klinefelter syndrome, testicular trauma, aging Leydig failure)
- •Polycystic Ovary Syndrome (elevated LH/FSH ratio)
- •Postmenopausal state
Low Levels (LH Low)
- •Secondary hypogonadism (hypopituitarism, hyperprolactinemia, anabolic steroid abuse)
- •Severe systemic illness
Technical Reference & Deep Dive
Biochemistry & Enzymatic Pathways
Longevity Risk Architecture & Epidemiology
Pre-Analytical Caveats & Diagnostic Workup
Pre-Analytical Considerations:
Blood draw must occur strictly between 7:00 AM and 9:00 AM to account for steep circadian cortisol and testosterone peaks. Ensure 8 hours of restful sleep prior; night shift work or sleep deprivation severely blunts endocrine pulsatility. Discontinue biotin supplements for 72 hours before thyroid or steroid testing to prevent false immunoassay results. For reproductive hormones in premenopausal females, precisely document the day of the menstrual cycle (Day 3 for baseline follicular, Day 21 for luteal).
Reflexive Testing Protocol:
- Free Hormone Equilibrium Dialysis or LC-MS/MS assay for direct bioavailable hormone quantification
- Pituitary trophic hormone panel (TSH, LH, FSH, ACTH, Prolactin) to differentiate primary vs central secondary endocrinopathies
- Autoantibody quantification (Thyroid Peroxidase Antibodies, Thyroglobulin Antibodies, 21-Hydroxylase Antibodies)
- Pelvic, testicular, or thyroid high-resolution ultrasound imaging to assess glandular parenchymal architecture
- Dynamic endocrine stimulation testing (Cosyntropin/ACTH stimulation test, Dexamethasone suppression test, GnRH test)
Clinical Citations & Primary Literature (1)
- [1]Evaluation and Differential Diagnosis of Hypogonadism - New England Journal of Medicine (2021). PMID: 33792050
Associated Longevity Guides & Clinical Calculators
Medicine 3.0Explore comprehensive evidence-based clinical protocols, testing costs, and algorithmic calculators that incorporate Luteinizing Hormone (LH) into overall healthspan optimization.