When should the LH test be done?

It is recommended if there are menstrual problems, difficulty conceiving, or abnormal hormonal symptoms.

What factors can affect the test results?

Results can be influenced by psychological factors, stress, certain medications, and weight changes.

What do high or low LH levels mean?

High levels may indicate problems such as polycystic ovary syndrome (PCOS), while low levels may suggest pituitary gland dysfunction.

Can I get the results on the same day?

This depends on the laboratory, but most labs provide results within one to two days.

Medical Laboratories

Luteinizing Hormone (LH) Test

A pivotal test for evaluating fertility and regulating the menstrual cycle, helping determine ovulation time and accurately diagnose causes of delayed conception.

Trusted medical contentUpdated: 25-04-2026Views: 51LHL-79

About this service

Luteinizing Hormone (LH) Test is a laboratory test used to measure the level of luteinizing hormone in the blood, which is produced by the pituitary gland. This hormone plays a key role in regulating the menstrual cycle in women by stimulating ovulation and coordinating the production of sex hormones such as estrogen and progesterone. In men, luteinizing hormone helps stimulate the production of testosterone, which affects fertility and sexual health. This test is used to diagnose various conditions, including menstrual disorders, infertility, polycystic ovary syndrome (PCOS), and to assess the function of the gonads. The test is performed by drawing a blood sample, and women are usually asked to take the test on specific days of their menstrual cycle to obtain accurate results. The LH test is part of a comprehensive evaluation of the reproductive system, and the results should be interpreted by a physician based on medical history and clinical symptoms.

Purpose Test

Function of the gonads: The test helps assess how the pituitary gland, ovaries, or testes are functioning, aiding in diagnosing any endocrine system imbalances.
Menstrual cycle disorders: Abnormal LH levels can indicate problems in the menstrual cycle, such as ovulation disorders or polycystic ovary syndrome (PCOS).
Fertility evaluation: This test is used to investigate causes of infertility in both women and men, as elevated or low LH levels may signal fertility issues.
Diagnosis of certain medical conditions: Such as PCOS, premature ovarian failure, or pituitary gland disorders.
Determining the phase of the menstrual cycle: LH levels surge right before ovulation, so the test can help pinpoint the ovulation period.
Assessment of other hormone levels: Often used alongside other tests, such as Follicle Stimulating Hormone (FSH) and sex hormones, to get a comprehensive view of reproductive health.

Recommended groups

Those experiencing menstrual cycle disorders, such as irregular or missed periods.
Cases related to fertility, such as difficulty conceiving or infertility.
Diagnosis of Polycystic Ovary Syndrome (PCOS), to check hormone levels.
Symptoms related to endocrine disorders, such as excess hair growth or acne.
Evaluation of fertility problems, such as infertility or low libido.
Diagnosis of conditions affecting testosterone production, like gonadal failure.
Issues related to the pituitary gland, if there are symptoms indicating hormonal imbalance.
Assessment of early or delayed puberty, used to determine the development of sexual characteristics.
Such as changes in weight, mood swings, or growth problems.

Symptoms indicative

Irregular or missed menstrual periods.
Abnormal menstrual cycles, such as very short or very long intervals between periods.
Difficulty conceiving or infertility in women or men.
Absence of ovulation.
Increased hair growth on the face or body (hirsutism).
Acne outbreaks.
Weight gain.
Severe mood swings.
Sudden increase or loss of weight.
Low libido or erectile dysfunction in men.
Decreased levels of sex hormones in women.
Delay in the appearance of secondary sexual characteristics during adolescence or early onset of these characteristics.

Normal Levels

Follicular Phase: 1.5 to 12.0 mIU/mL (milli-international units per milliliter)
Ovulatory Phase: 12.0 to 50.0 mIU/mL
Luteal Phase: 0.5 to 16.0 mIU/mL
Normal LH levels: 1.5 to 9.3 mIU/mL
LH levels are generally very low during childhood and vary depending on the stage of development.
Normal ranges may slightly vary depending on the laboratory and testing methods used, so it’s important to refer to the specific reference values provided by the lab.
It is important to consult a physician to properly interpret the results, as several factors—including age, menstrual cycle phase, medications, and health conditions—can influence LH levels.

Frequently Asked Questions

Short answers to the FAQs published with this service.

What is the purpose of the LH test?

It is used to assess the function of the reproductive glands, identify causes of infertility, and monitor menstrual health.

How is the LH test performed?

A blood sample is drawn in a laboratory, usually in the morning.

Are there any preparations before taking the test?

Generally, no special preparations are needed, but it may be recommended to perform the test on specific days of the menstrual cycle for women.

What are the normal LH levels?

Normal levels vary by age and gender, usually ranging between 1.0 to 20.0 IU/L (International Units per Liter).

Luteinizing Hormone (LH) Test

About this service

Purpose Test

Recommended groups

Symptoms indicative

Normal Levels

What is included?

Conditions and notices

Frequently Asked Questions

References and additional resources

Scientific references

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