Quick answer: LH (luteinizing hormone) is a pituitary hormone that triggers ovulation in women and testosterone production in men. LH surges mid-cycle before ovulation. A high LH-to-FSH ratio can be seen in PCOS, high LH is typical after menopause, and low LH can point to pituitary or hypothalamic issues or low testosterone of central origin.
What is LH?
LH is made by the pituitary. In women it triggers ovulation and progesterone production; in men it signals the testes to make testosterone. This marker is part of the Healthspan Assessment panel available to my 1-on-1 patients.
Why LH matters
- Ovulation
- Progesterone production after ovulation
- Testosterone production in men
- Fertility evaluation
Understanding your result
Reference ranges vary by lab, age and sex. Your provider interprets your result against the lab’s range and your overall picture, rather than chasing a single number. Functional labs are optional. They can be helpful in more complex cases, and in my practice they are available only to patients working 1-on-1 with me.
What low LH can mean
- Pituitary or hypothalamic issues
- Under-eating, over-exercise or high stress
- Low testosterone of central origin in men
- Opioid or steroid use
What high LH can mean
- Mid-cycle surge (normal)
- PCOS (often higher relative to FSH)
- Menopause
- In men, testicular problems
What affects LH
- Cycle day
- Hormonal birth control
- Energy availability and stress
- Body weight
Ways to support healthy levels
- Eat enough and manage stress to support ovulation
- Support insulin sensitivity if you have PCOS (see PCOS natural treatment)
- Men with low testosterone should have LH checked to find the cause
LH and healthy aging
LH patterns reflect how the brain and reproductive organs communicate. That signaling changes with age and stress, affecting hormones that protect bone, muscle and metabolism.
Related tests and articles: FSH, progesterone.
When to see a naturopathic doctor
- Irregular cycles or trouble conceiving
- Signs of PCOS
- Men with low testosterone symptoms
- Missed periods
See a medical provider promptly for absent periods for three months (after ruling out pregnancy), headaches with vision changes, or loss of sexual development in teens.
Want help making sense of your labs?
A free 15-minute consultation with Dr. Kneessi. No cost, no obligation. In-office in Odenton, MD or by telehealth.
Frequently asked questions
What does a high LH to FSH ratio mean?
It can be seen in PCOS, though it is not required for diagnosis.
When does LH surge?
It rises shortly before ovulation.
Why test LH in men?
To find out whether low testosterone comes from the testes or the brain.
Do ovulation tests measure LH?
Yes. Home ovulation kits detect the LH surge in urine.
Sources
- Direito A, et al. Relationships between the luteinizing hormone surge and other characteristics of the menstrual cycle in normally ovulating women. Fertil Steril 2013. PMID: 22999798. https://pubmed.ncbi.nlm.nih.gov/22999798/
- Teede HJ, et al. Recommendations from the 2023 international evidence-based guideline for the assessment and management of polycystic ovary syndrome. J Clin Endocrinol Metab 2023. PMID: 37580314. https://pmc.ncbi.nlm.nih.gov/articles/PMC10505534/
- Bhasin S, et al. Testosterone therapy in men with hypogonadism: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metab 2018. PMID: 29562364. https://pubmed.ncbi.nlm.nih.gov/29562364/
- MedlinePlus: Luteinizing Hormone (LH) Levels Test
- NICHD: Polycystic Ovary Syndrome (PCOS)
This article is for educational purposes only and is not medical advice. It does not replace an individual evaluation. Talk with your healthcare provider before starting supplements or changing medications, especially if you are pregnant, nursing, or managing a health condition.
Free: The 28-Day Longevity Reset
A simple day-by-day email guide to sleep, movement, food, and daily habits that support healthy aging. It’s free, and you can unsubscribe anytime.
Get the free guide
