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Luteinizing Hormone (LH) Unit Converter
Luteinizing Hormone (LH) is a critical gonadotropin produced by the pituitary gland. In women, LH triggers ovulation (the mid-cycle surge) and stimulates the production of progesterone by the corpus luteum. In men, LH stimulates the Leydig cells in the testes to produce testosterone.[Image of the female hormonal cycle showing LH and FSH surges]
Clinically, LH levels are measured, often alongside FSH, to investigate infertility, menstrual irregularities (e.g., PCOS), and pituitary/gonadal function. As a glycoprotein hormone, its biological activity is measured in International Units (IU/L or mIU/mL). Note that mass/molar conversions for LH are highly variable and should be avoided clinically.
Activity Units
RecommendedInternational Units per liter (Numerically IU/L = mIU/mL).
Other Equivalents
Clinical Context
Reference Ranges (Women):
• Follicular Phase: ≈ 1.5 – 8.0 IU/L
• Ovulatory Surge: ≈ 20 – 100 IU/L
• Postmenopausal: ≈ 10 – 60 IU/L
In women, a sudden spike in LH is often detected by ovulation predictor kits. A high LH/FSH ratio (> 2:1 or > 3:1) is highly suggestive of Polycystic Ovary Syndrome (PCOS). Conversions between International Units and mass/molar units are assay-dependent and not standardized.
Clinical References
How to Use This Calculator
Follow these steps to get accurate clinical conversions instantly.
Enter Values
Input your laboratory results into the corresponding unit field (e.g., IU/L). You can use either dot or comma decimals.
Automatic Conversion
The calculator uses the exact 1:1 relationship for activity units (IU/L = mIU/mL).
Verify Units
Check the Activity Units section. For LH, IU/L is the SI standard for reporting.
Reset
Use the Clear button to reset all fields before starting a new calculation.
Frequently Asked Questions & Tips
Yes. The units are numerically equivalent: 1 IU/L = 1 mIU/mL = 1 mU/mL.
Because LH is a large glycoprotein with varying carbohydrate structures, its molecular weight and the resulting mass conversion factor are highly variable depending on the assay kit used.