Decreased LH

Subnormal serum luteinizing hormone (LH) concentrations below the gender- and phase-specific reference range, reflecting impaired gonadal stimulation and potential disruption of reproductive hormone regulation.

• Follicular phase 1.6-12.6 IU/L

• Ovulation peak 14-95.6 IU/L

• Luteal phase 1-16.3 IU/L

• Menopause 16-66 IU/L

• Adult male 1.2-8 IU/L

Causes

• Hypothalamic or pituitary dysfunction

  • Pituitary tumor

  • Prolactinoma

  • Sheehan syndrome

• Chronic stress

• Low body mass index (BMI) / malnutrition

• Excessive exercise

• Medications: Opioids, glucocorticoids, oral contraceptives, testosterone

• Genetic causes: Kallmann syndrome