What are normal TSH levels. How do TSH levels change with age and pregnancy. What symptoms indicate hypothyroidism or hyperthyroidism. How is TSH testing used to diagnose thyroid disorders.

The Importance of TSH in Thyroid Function

Thyroid-stimulating hormone (TSH) plays a crucial role in regulating thyroid function. Produced by the pituitary gland, TSH stimulates the thyroid gland to produce and release thyroid hormones. These hormones are essential for numerous bodily functions, including metabolism, heart rate, and body temperature regulation.

TSH levels in the blood serve as a reliable indicator of thyroid health. When thyroid hormone levels are low, the pituitary gland increases TSH production to stimulate the thyroid. Conversely, when thyroid hormone levels are high, TSH production decreases. This feedback loop helps maintain optimal thyroid function.

Normal TSH Ranges and Variations

Understanding normal TSH ranges is crucial for interpreting test results. While the generally accepted normal range is between 0.4 and 4.0 milliunits per liter (mU/L), it’s important to note that this range can vary based on factors such as age, pregnancy status, and individual health conditions.

Age-Related TSH Changes

TSH levels tend to increase with age. This natural progression is important to consider when evaluating thyroid function in older adults. For instance:

• Newborns typically have the highest TSH levels
• Children and young adults generally have lower levels
• Older adults may have slightly elevated levels compared to younger individuals

In fact, research suggests that 7-14% of people over 60 may have TSH levels above the upper limit of standard reference ranges. This highlights the importance of age-specific interpretations when assessing thyroid health.

TSH During Pregnancy

Pregnancy significantly alters thyroid hormone dynamics. During pregnancy, TSH levels typically decrease due to the influence of pregnancy hormones. This reduction is essential for fetal brain and nervous system development.

How do pregnancy-specific TSH ranges differ from non-pregnant ranges? Doctors generally use lower reference ranges during pregnancy:

• The lower TSH range is decreased by approximately 0.4 mU/L
• The upper limit is reduced by about 0.5 mU/L

Careful monitoring of TSH levels throughout pregnancy is crucial, as abnormal levels can increase the risk of complications such as preeclampsia, premature birth, and low birth weight.

Hypothyroidism: When TSH Levels Are High

High TSH levels often indicate hypothyroidism, a condition where the thyroid gland produces insufficient hormones. When thyroid hormone production is low, the pituitary gland compensates by increasing TSH production.

What are the common symptoms of hypothyroidism? Individuals with this condition may experience:

• Fatigue and weakness
• Weight gain
• Increased sensitivity to cold
• Dry skin and hair
• Depression
• Constipation
• Irregular or heavy menstrual periods
• Fertility problems

It’s important to note that symptoms can vary in severity and may develop gradually over time. Regular TSH testing can help detect hypothyroidism early, even before noticeable symptoms appear.

Hyperthyroidism: When TSH Levels Are Low

Low TSH levels typically indicate hyperthyroidism, also known as an overactive thyroid. In this condition, the thyroid gland produces excessive amounts of thyroid hormones, leading to a decrease in TSH production by the pituitary gland.

What symptoms might someone with hyperthyroidism experience? Common signs include:

• Unexplained weight loss
• Rapid heartbeat or palpitations
• Increased appetite
• Nervousness and anxiety
• Tremors in hands and fingers
• Excessive sweating
• Changes in menstrual patterns
• Increased sensitivity to heat

As with hypothyroidism, the severity and combination of symptoms can vary among individuals. Prompt diagnosis through TSH testing is crucial for effective management of hyperthyroidism.

TSH Testing: A Valuable Diagnostic Tool

TSH testing serves as a primary tool for diagnosing and monitoring thyroid disorders. This simple blood test provides valuable insights into thyroid function and helps guide treatment decisions.

How does TSH testing work in clinical practice? Typically, doctors will order a TSH test as part of a routine check-up or when thyroid dysfunction is suspected. If TSH levels are abnormal, additional tests may be performed to confirm the diagnosis and determine the underlying cause.

These additional tests may include:

• Free T4 (thyroxine) test
• Free T3 (triiodothyronine) test
• Thyroid antibody tests
• Thyroid ultrasound

The combination of TSH testing and these supplementary examinations allows for a comprehensive evaluation of thyroid health and function.

Gender Differences in Thyroid Function

While research has not consistently shown significant differences in TSH levels between males and females, thyroid disorders are generally more prevalent in women. Understanding these gender-related distinctions is crucial for accurate diagnosis and treatment.

How do thyroid disorders affect men and women differently? Consider the following:

• Women are more likely to experience thyroid dysfunction, with 1 in 8 women developing thyroid problems at some point in their lives.
• The risk of thyroid issues in women increases during pregnancy and around menopause.
• Some studies suggest that TSH levels may be slightly higher in females, although age and other factors play a more significant role in determining TSH levels.
• Thyroid conditions can be associated with sexual dysfunction in both genders, but this may affect a higher percentage of men with hypothyroidism (59-63%) compared to women (22-46%).

These gender-related differences emphasize the importance of individualized approaches to thyroid health assessment and management.

Thyroid Health in Children and Adolescents

Thyroid function and TSH levels undergo significant changes throughout childhood and adolescence. Understanding these age-related variations is crucial for accurate diagnosis and treatment of thyroid disorders in younger populations.

How do TSH levels change as children grow? Here’s a general overview:

• Newborns have the highest TSH levels, which gradually decrease over time.
• By age 5, TSH levels typically stabilize within a range similar to adult levels.
• During puberty, slight fluctuations in TSH levels may occur due to hormonal changes.

It’s important to note that reference ranges for children may differ from those used for adults. For instance, mild hypothyroidism in children is often defined as TSH levels between 4.5-10 mU/L after the newborn phase.

Regular monitoring of thyroid function in children, especially those with risk factors or symptoms of thyroid dysfunction, is essential for early detection and intervention.

Treating Thyroid Disorders: Beyond TSH Testing

While TSH testing is invaluable for diagnosing thyroid disorders, treatment often involves more than just normalizing TSH levels. The goal of thyroid disorder treatment is to restore overall thyroid function and alleviate symptoms.

What are the common treatment approaches for thyroid disorders?

Hypothyroidism Treatment

For hypothyroidism, the standard treatment involves thyroid hormone replacement therapy. This typically includes:

• Levothyroxine: A synthetic form of the T4 hormone
• Regular monitoring and dose adjustments to achieve optimal hormone levels
• Lifestyle modifications, such as dietary changes and stress management

Hyperthyroidism Treatment

Treatment for hyperthyroidism may involve:

• Anti-thyroid medications to reduce hormone production
• Radioactive iodine therapy to shrink the thyroid gland
• In some cases, surgical removal of the thyroid (thyroidectomy)
• Beta-blockers to manage symptoms like rapid heart rate

The choice of treatment depends on factors such as the underlying cause of hyperthyroidism, the severity of symptoms, and the patient’s overall health status.

The Future of Thyroid Testing and Treatment

As our understanding of thyroid function continues to evolve, so do the methods for diagnosing and treating thyroid disorders. Emerging research and technologies are paving the way for more precise and personalized approaches to thyroid health management.

What advancements can we expect in thyroid care? Some promising areas include:

• Genetic testing to identify individuals at higher risk for thyroid disorders
• Development of more sensitive and specific biomarkers for thyroid dysfunction
• Improved imaging techniques for better visualization of thyroid structure and function
• Personalized medicine approaches that take into account individual genetic and environmental factors

These advancements hold the potential to revolutionize thyroid care, leading to earlier detection, more targeted treatments, and improved outcomes for patients with thyroid disorders.

Lifestyle Factors Affecting Thyroid Health

While TSH levels and thyroid function are primarily regulated by internal biological processes, various lifestyle factors can influence thyroid health. Understanding and addressing these factors can play a crucial role in maintaining optimal thyroid function and managing thyroid disorders.

What lifestyle elements can impact thyroid health?

Diet and Nutrition

Certain nutrients are essential for proper thyroid function:

• Iodine: Critical for thyroid hormone production
• Selenium: Supports thyroid hormone metabolism
• Zinc: Aids in thyroid hormone synthesis
• Vitamin D: Plays a role in thyroid hormone action

Conversely, excessive consumption of certain foods, such as those high in goitrogens (e.g., raw cruciferous vegetables), may interfere with thyroid function in some individuals.

Stress Management

Chronic stress can disrupt the delicate balance of hormones in the body, potentially affecting thyroid function. Implementing stress-reduction techniques such as meditation, yoga, or regular exercise can support overall thyroid health.

Environmental Factors

Exposure to certain environmental toxins and chemicals may impact thyroid function:

• Endocrine disruptors found in some plastics and personal care products
• Heavy metals like mercury and lead
• Excessive radiation exposure

Minimizing exposure to these factors and supporting the body’s natural detoxification processes can help maintain optimal thyroid health.

Sleep and Circadian Rhythms

Quality sleep and maintaining regular circadian rhythms are important for overall hormonal balance, including thyroid function. Establishing good sleep hygiene and consistent sleep patterns can support thyroid health.

By addressing these lifestyle factors in conjunction with medical treatment, individuals can take a comprehensive approach to managing their thyroid health and optimizing TSH levels.

Patient Education and Self-Advocacy in Thyroid Care

Empowering patients with knowledge about thyroid health and TSH testing is crucial for effective management of thyroid disorders. Informed patients are better equipped to participate actively in their care and communicate effectively with healthcare providers.

How can patients become more engaged in their thyroid health management?

Understanding TSH Test Results

Patients should be encouraged to:

• Familiarize themselves with their TSH test results and reference ranges
• Keep a record of their TSH levels over time
• Understand how factors like age and pregnancy can affect TSH levels

Recognizing Symptoms

Education about the symptoms of hypo- and hyperthyroidism can help patients:

• Identify potential thyroid issues early
• Communicate changes in their health effectively to their healthcare provider
• Distinguish between thyroid-related symptoms and those of other conditions

Medication Management

For patients on thyroid medication, understanding the importance of:

• Consistent medication timing and dosage
• Potential interactions with other medications or supplements
• The need for regular monitoring and dose adjustments

Lifestyle Modifications

Encouraging patients to take an active role in their thyroid health through:

• Adopting a thyroid-friendly diet
• Incorporating stress-reduction techniques
• Maintaining a healthy weight and regular exercise routine

Advocating for Comprehensive Care

Empowering patients to:

• Ask questions about their thyroid health and treatment options
• Seek second opinions when necessary
• Discuss the potential benefits of additional testing or alternative treatments

By fostering patient education and self-advocacy, healthcare providers can enhance the quality of thyroid care and improve outcomes for individuals with thyroid disorders.

Low to high ranges, symptoms, and what they mean

The thyroid-stimulating hormone (TSH) test measures the amount of TSH in the blood. TSH levels convey how well a person’s thyroid is functioning.

Doctors can use TSH test results to diagnose thyroid disorders, such as hypothyroidism and hyperthyroidism.

The pituitary gland produces TSH, which is a hormone that stimulates the thyroid gland.

The thyroid is a butterfly-shaped gland in the throat. It produces hormones that help regulate many bodily functions, such as metabolism, heart rate, and body temperature.

This article describes the TSH test and results. We also discuss what high and low TSH levels indicate and available treatments.

Share on PinterestMNT-infographic_guide infographic by Diego Sabogal 1401179-TSH-levels-original

The normal range depends on a person’s age and whether they are pregnant.

The ranges tend to increase as a person gets older. Research has not shown a consistent difference in TSH levels between males and females.

However, according to the American Thyroid Association, doctors generally consider levels are within a normal range between 0.4–4.0 milliunits per liter (mU/l).

The following table provides estimates of TSH levels that are normal, low (indicating hyperthyroidism), and high (indicating hypothyroidism):

Many labs use these reference values.

However, there is some debate about these ranges. The author of a 2016 review suggests that normal levels are more likely to fall between 0.5–2.5 milli-international units (mIU) per milliliter.

Females are more likely to experience thyroid dysfunction than males. The Office on Women’s Health reports that 1 in 8 females experience thyroid problems at some point. This includes hyperthyroidism and hypothyroidism. The risk of thyroid problems increases during pregnancy and around menopause.

Research does not show a consistent difference in TSH levels between males and females. However, some evidence suggests that TSH levels are generally higher in females. For example, studies in 2020 investigating Chinese and French populations suggest that TSH levels are higher in females, but other factors, such as age, are more likely to affect TSH levels.

In some people, thyroid conditions are linked with sexual dysfunction. This may affect more males than females. According to a 2019 study, 59–63% of males with hypothyroidism also experience sexual dysfunction, compared with 22–46% of females who have hypothyroidism.

Blood TSH levels tend to increase as people get older, with evidence noting that hypothyroidism is the most common thyroid condition in people over 60 and steadily increases with age.

Research involving older adults suggests that roughly 7–14% of people may have TSH levels above the upper limit of reference ranges.

Pregnancy hormones naturally increase the levels of certain thyroid hormones in the blood. This is essential for the development of the fetal brain and nervous system.

At the same time, the levels of TSH in the blood decrease. As a result, doctors use lower reference ranges during pregnancy. The lower TSH range is decreased by around 0.4 mU/l, and the upper limit reduced by approximately 0.5 mU/l.

Levels of TSH in the blood increase gradually during the second and third trimesters, but they remain lower than normal levels in women who are not pregnant.

Doctors carefully monitor TSH levels throughout pregnancy. Having unusually high or low levels can affect the risk of miscarriage and cause pregnancy-related complications, such as:

• preeclampsia
• premature birth
• low birth weight
• congestive heart failure

TSH levels are highest at birth and gradually decrease as a child gets older. As such, TSH levels can vary among children. After the newborn phase, health experts may define mild hypothyroidism in children as TSH levels ranging between 4.5–10 mU/l.

The following table shows TSH levels for children by age, according to an older study using data from 512 healthy children:

High TSH levels indicate hypothyroidism. People develop hypothyroidism when their thyroid produces low levels of hormones.

When someone’s thyroid gland does not produce enough hormones, the pituitary gland produces more TSH to compensate.

Symptoms of hypothyroidism may include:

• fatigue
• weight gain
• swelling of the face and neck
• increased sensitivity to cold temperatures
• dry skin
• thinning hair
• a slow heart rate
• irregular or heavy menstrual periods
• fertility problems
• depression
• constipation

Low TSH levels indicate hyperthyroidism. This is also known as an overactive thyroid.

If a person’s thyroid gland is secreting levels of hormones that are too high, the pituitary gland produces less TSH.

Symptoms of hyperthyroidism can include:

• irregular or rapid heartbeat
• muscle weakness
• nervousness or irritability
• difficulty sleeping
• frequent bowel movements or diarrhea
• weight loss
• mood changes

The TSH test involves a healthcare professional drawing blood from a vein in the inner arm. They then send the blood sample for laboratory testing.

Usually, people do not need to prepare for a TSH test. However, if the doctor is checking the blood for more than one issue, a person may need to fast or prepare in another way. The doctor will provide this information beforehand.

A TSH test is often the best way to monitor thyroid function. However, if a person has abnormally high or low TSH levels, the doctor may need to perform at least one other diagnostic test to identify the underlying cause. These tests look at levels of specific thyroid hormones and antibodies.

In addition to age, sex, and pregnancy, many other factors can also affect TSH levels. Evidence suggests that genetic, environmental, or intrinsic factors can alter TSH levels. Some of these factors may include:

• other conditions occurring at the same time
• medications
• supplements
• ethnicity
• diet and iodine status
• time of day and time of year
• autoantibodies and heterophilic antibodies
• smoking
• pollutants

Doctors can treat hypothyroidism with medications, such as levothyroxine, that replace the missing thyroid hormones.

A person should take this medication once a day or as prescribed. The doctor will monitor how well the treatment is working by running additional blood tests every few months.

According to the Food and Drug Administration (FDA), people should take levothyroxine once a day: in the morning and on an empty stomach, at least half an hour before eating.

The FDA also recommends that a person informs their doctor if they eat soybean flour, walnuts, dietary fiber, or cottonseed meal — these foods can affect how the body processes levothyroxine. Drinking grapefruit juice may also delay the absorption of levothyroxine.

Hyperthyroidism treatments focus on reducing thyroid hormone levels to prevent long-term health complications.

A person may need to take beta-blockers and antithyroid medications.

Another effective treatment is radioiodine therapy. This involves taking a capsule or liquid that contains radioactive iodine-131, which destroys cells that produce thyroid hormones. However, people who take radioiodine therapy may develop hypothyroidism in the future.

Surgical removal of the thyroid gland can treat severe hyperthyroidism. Doctors often reserve this for individuals who cannot take first-line medications and severe cases of hyperthyroidism.

A TSH test measures the amount of the hormone in the blood. Doctors can use the results to diagnose thyroid conditions, such as hypothyroidism and hyperthyroidism.

Normal TSH ranges can vary widely, depending on a person’s age, sex, and weight. Reference TSH ranges remain controversial, but for most people, the normal range falls between 0.4 and 4.0 mU/l.

Having an overactive or underactive thyroid can cause health issues that interfere with a person’s daily life. During pregnancy, unusually high or low TSH levels can lead to complications.

A doctor can provide more information about the TSH test and interpreting the results.

Low to high ranges, symptoms, and what they mean

The thyroid-stimulating hormone (TSH) test measures the amount of TSH in the blood. TSH levels convey how well a person’s thyroid is functioning.

Doctors can use TSH test results to diagnose thyroid disorders, such as hypothyroidism and hyperthyroidism.

The pituitary gland produces TSH, which is a hormone that stimulates the thyroid gland.

The thyroid is a butterfly-shaped gland in the throat. It produces hormones that help regulate many bodily functions, such as metabolism, heart rate, and body temperature.

This article describes the TSH test and results. We also discuss what high and low TSH levels indicate and available treatments.

Share on PinterestMNT-infographic_guide infographic by Diego Sabogal 1401179-TSH-levels-original

The normal range depends on a person’s age and whether they are pregnant.

The ranges tend to increase as a person gets older. Research has not shown a consistent difference in TSH levels between males and females.

However, according to the American Thyroid Association, doctors generally consider levels are within a normal range between 0.4–4.0 milliunits per liter (mU/l).

The following table provides estimates of TSH levels that are normal, low (indicating hyperthyroidism), and high (indicating hypothyroidism):

Hyperthyroidism	Normal	Mild hypothyroidism	Hypothyroidism
0–0. 4	0.4–4	4–10	10

Many labs use these reference values.

However, there is some debate about these ranges. The author of a 2016 review suggests that normal levels are more likely to fall between 0.5–2.5 milli-international units (mIU) per milliliter.

Females are more likely to experience thyroid dysfunction than males. The Office on Women’s Health reports that 1 in 8 females experience thyroid problems at some point. This includes hyperthyroidism and hypothyroidism. The risk of thyroid problems increases during pregnancy and around menopause.

Research does not show a consistent difference in TSH levels between males and females. However, some evidence suggests that TSH levels are generally higher in females. For example, studies in 2020 investigating Chinese and French populations suggest that TSH levels are higher in females, but other factors, such as age, are more likely to affect TSH levels.

In some people, thyroid conditions are linked with sexual dysfunction. This may affect more males than females. According to a 2019 study, 59–63% of males with hypothyroidism also experience sexual dysfunction, compared with 22–46% of females who have hypothyroidism.

Blood TSH levels tend to increase as people get older, with evidence noting that hypothyroidism is the most common thyroid condition in people over 60 and steadily increases with age.

Research involving older adults suggests that roughly 7–14% of people may have TSH levels above the upper limit of reference ranges.

Pregnancy hormones naturally increase the levels of certain thyroid hormones in the blood. This is essential for the development of the fetal brain and nervous system.

At the same time, the levels of TSH in the blood decrease. As a result, doctors use lower reference ranges during pregnancy. The lower TSH range is decreased by around 0.4 mU/l, and the upper limit reduced by approximately 0.5 mU/l.

Levels of TSH in the blood increase gradually during the second and third trimesters, but they remain lower than normal levels in women who are not pregnant.

Doctors carefully monitor TSH levels throughout pregnancy. Having unusually high or low levels can affect the risk of miscarriage and cause pregnancy-related complications, such as:

• preeclampsia
• premature birth
• low birth weight
• congestive heart failure

TSH levels are highest at birth and gradually decrease as a child gets older. As such, TSH levels can vary among children. After the newborn phase, health experts may define mild hypothyroidism in children as TSH levels ranging between 4.5–10 mU/l.

The following table shows TSH levels for children by age, according to an older study using data from 512 healthy children:

Age	Reference ranges (mU/l)
Day of birth	3.84–11.75
1 month	1.18–3.57
1 year	1.17–3.55
5 years	1.15–3.47
12 years	1. 09–3.31
18 years	1.05–3.16

High TSH levels indicate hypothyroidism. People develop hypothyroidism when their thyroid produces low levels of hormones.

When someone’s thyroid gland does not produce enough hormones, the pituitary gland produces more TSH to compensate.

Symptoms of hypothyroidism may include:

• fatigue
• weight gain
• swelling of the face and neck
• increased sensitivity to cold temperatures
• dry skin
• thinning hair
• a slow heart rate
• irregular or heavy menstrual periods
• fertility problems
• depression
• constipation

Low TSH levels indicate hyperthyroidism. This is also known as an overactive thyroid.

If a person’s thyroid gland is secreting levels of hormones that are too high, the pituitary gland produces less TSH.

Symptoms of hyperthyroidism can include:

• irregular or rapid heartbeat
• muscle weakness
• nervousness or irritability
• difficulty sleeping
• frequent bowel movements or diarrhea
• weight loss
• mood changes

The TSH test involves a healthcare professional drawing blood from a vein in the inner arm. They then send the blood sample for laboratory testing.

Usually, people do not need to prepare for a TSH test. However, if the doctor is checking the blood for more than one issue, a person may need to fast or prepare in another way. The doctor will provide this information beforehand.

A TSH test is often the best way to monitor thyroid function. However, if a person has abnormally high or low TSH levels, the doctor may need to perform at least one other diagnostic test to identify the underlying cause. These tests look at levels of specific thyroid hormones and antibodies.

In addition to age, sex, and pregnancy, many other factors can also affect TSH levels. Evidence suggests that genetic, environmental, or intrinsic factors can alter TSH levels. Some of these factors may include:

• other conditions occurring at the same time
• medications
• supplements
• ethnicity
• diet and iodine status
• time of day and time of year
• autoantibodies and heterophilic antibodies
• smoking
• pollutants

Doctors can treat hypothyroidism with medications, such as levothyroxine, that replace the missing thyroid hormones.

A person should take this medication once a day or as prescribed. The doctor will monitor how well the treatment is working by running additional blood tests every few months.

According to the Food and Drug Administration (FDA), people should take levothyroxine once a day: in the morning and on an empty stomach, at least half an hour before eating.

The FDA also recommends that a person informs their doctor if they eat soybean flour, walnuts, dietary fiber, or cottonseed meal — these foods can affect how the body processes levothyroxine. Drinking grapefruit juice may also delay the absorption of levothyroxine.

Hyperthyroidism treatments focus on reducing thyroid hormone levels to prevent long-term health complications.

A person may need to take beta-blockers and antithyroid medications.

Another effective treatment is radioiodine therapy. This involves taking a capsule or liquid that contains radioactive iodine-131, which destroys cells that produce thyroid hormones. However, people who take radioiodine therapy may develop hypothyroidism in the future.

Surgical removal of the thyroid gland can treat severe hyperthyroidism. Doctors often reserve this for individuals who cannot take first-line medications and severe cases of hyperthyroidism.

A TSH test measures the amount of the hormone in the blood. Doctors can use the results to diagnose thyroid conditions, such as hypothyroidism and hyperthyroidism.

Normal TSH ranges can vary widely, depending on a person’s age, sex, and weight. Reference TSH ranges remain controversial, but for most people, the normal range falls between 0.4 and 4.0 mU/l.

Having an overactive or underactive thyroid can cause health issues that interfere with a person’s daily life. During pregnancy, unusually high or low TSH levels can lead to complications.

A doctor can provide more information about the TSH test and interpreting the results.

Thyroid stimulating hormone (TSH)

Thyroid stimulating hormone (TSH) is the main regulator of thyroid function, synthesized by the pituitary gland, a small gland located on the lower surface of the brain. Its main function is to maintain a constant concentration of thyroid hormones – thyroid hormones that regulate the processes of energy production in the body. When their blood levels decrease, the hypothalamus releases a hormone that stimulates the secretion of TSH by the pituitary gland.

Russian synonyms

Thyrostimulating hormone, thyrotropin, TTU.

Synonyms English

Thyroid-stimulating Hormone (THS), Thyrotropin.

Research method

Electrochemiluminescent immunoassay.

Detection range: 0.005 – 1000 µIU/ml.

Units

µIU/mL (microinternational unit per milliliter).

What biomaterial can be used for research?

Venous blood.

How to properly prepare for an examination?

• Children under 1 year of age do not eat for 30-40 minutes before the test.
• Do not eat for 2-3 hours before the study, you can drink clean still water.
• Exclude (in agreement with the doctor) taking thyroid hormones, iodine preparations within 72 hours before the study.
• Exclude (in agreement with the doctor) the use of steroid hormones within 48 hours before the study.
• Avoid physical and emotional overexertion within 24 hours prior to the study.
• Do not smoke for 3 hours prior to the study.

Study Overview

Thyroid stimulating hormone (TSH) is produced by the pituitary gland, a small gland located on the lower surface of the brain behind the sinus cavity. It regulates the production of thyroid hormones (thyroxine and triiodothyronine) according to the “feedback system”, which allows you to maintain a stable concentration of these hormones in the blood. With a decrease in the concentration of thyroid hormones, the secretion of thyroid-stimulating hormone increases and their production by the thyroid gland is stimulated, and vice versa – with an increase in the concentration of thyroxine and triiodothyronine, the secretion of thyroid-stimulating hormone decreases. Thyroid hormones are the main regulators of energy consumption in the body, and maintaining their concentration at the required level is extremely important for the normal functioning of almost all organs and systems.

Pituitary dysfunction can cause an increase or decrease in thyroid-stimulating hormone levels. With an increase in its concentration, thyroid hormones are released into the blood in abnormal amounts, causing hyperthyroidism. With a decrease in the concentration of thyroid-stimulating hormone, the production of thyroid hormones also decreases and symptoms of hypothyroidism develop.

The causes of impaired production of thyroid-stimulating hormone may be diseases of the hypothalamus, which begins to produce increased or decreased amounts of thyreoliberin, a regulator of TSH secretion by the pituitary gland. Diseases of the thyroid gland, accompanied by a violation of the secretion of thyroid hormones, can indirectly (by a feedback mechanism) affect the secretion of thyroid-stimulating hormone, causing a decrease or increase in its concentration in the blood. Thus, the study of TSH is one of the most important tests for hormones.

What is research used for?

• To determine the state of the thyroid gland, an indirect assessment of the production of thyroid hormones.
• To control the therapy of thyroid diseases.
• For the diagnosis of thyroid dysfunction in newborns.
• For diagnosing female infertility and monitoring its treatment.

When is the test scheduled?

1. With an enlarged thyroid gland, as well as with symptoms of hyper- and hypothyroidism.
   • Symptoms of hyperthyroidism:
     • palpitations,
     • increased anxiety,
     • weight loss,
     • insomnia,
     • hand shake,
     • weakness, fatigue,
     • diarrhea,
     • intolerance to bright light,
     • decreased visual acuity,
     • puffiness around the eyes, their dryness, hyperemia, bulging.
   • Symptoms of hypothyroidism:
     • dry skin,
     • constipation,
     • cold intolerance,
     • edema,
     • hair loss,
     • weakness, fatigue,
     • menstrual disorders in women.

• Tests may be ordered at regular intervals to monitor the effectiveness of thyroid therapy. TSH levels are often assessed in newborns at risk for thyroid disease.

What do the results mean?

Reference values ​​

Causes of elevated thyroid-stimulating hormone levels:

• hypothyroidism (primary and secondary),
• pituitary tumor (thyrotropinoma, basophilic adenoma),
• Hashimoto’s thyroiditis,
• syndrome of unregulated secretion of TSH,
• thyrotropin-secreting tumors of the lung,
• adrenal insufficiency,
• preeclampsia,
• lead poisoning,
• mental illness.

Causes of a decrease in the concentration of thyroid-stimulating hormone:

• diffuse toxic goiter,
• TSH-independent thyrotoxicosis,
• thyrotoxic adenoma (Plummer’s disease),
• hyperthyroidism of pregnancy,
• autoimmune thyroiditis with manifestations of thyrotoxicosis,
• mental illness,
• cachexia.

Elevated and decreased levels of thyroid-stimulating hormone indicate thyroid dysfunction, but it is often impossible to determine the exact cause from TSH levels alone. Usually, for this, the level of thyroxine (T4) and triiodothyronine (T3) is additionally determined.

Important Notes

• The following drugs may increase thyroid-stimulating hormone levels: phenytoin, atenolol, clomiphene, motilium, metoprolol, valproic acid, propranolol, amiodarone, calcitonin, prednisolone, morphine, phenothiazine derivatives, benserazide, aminoglutethimide, metoclopramide, furosemide, iodides, lovastatin, methimazole, difenin, rifampicin.
• The level of thyroid-stimulating hormone reflects the situation in the pituitary – thyroid gland over the past 3-6 weeks, so it is advisable to conduct a control determination of the concentration of TSH in the blood 2 months after adjusting the dose of drugs that affect the hormone level.
• The level of thyroid-stimulating hormone can be affected by physical and emotional stress, acute infectious diseases.
• Some studies have shown changes in TSH levels during the day. Therefore, in order to monitor the concentration of TSH, it is recommended to take the test at the same time of day.
• The level of TSH in pregnant women in the third trimester may be elevated.

Also recommended

• Triiodothyronine total (T3 total
• Thyroxine general (T4 general)
• Free thyroxine (T4 free)
• Triiodothyronine free (T3 free)
• Thyroid peroxidase antibodies (anti-TPO)
• Anti-thyroglobulin antibodies (antiTG)

Who orders the examination?

Endocrinologist, internist, pediatrician, gynecologist, neurologist, surgeon.

SANAS Medical Center in Vladivostok

The role of hormones in human life is great. They control the functioning of vital organs. Violation of their balance leads to malfunctions in the body and various diseases that can be asymptomatic at first, and then lead to very serious complications if tests are not taken on time.

These signs indicate that the thyroid gland needs to be checked:

• Enlarged lymph nodes

• Decreased libido or potency in men

• Diseases of the heart

• Depression

• Menstrual irregularity in women

• Hair loss

• Developmental delay (mental and physical in children).

The thyroid gland produces two hormones: thyroxine and triiodothyronine. They are responsible for many vital functions: they regulate the activity of the brain, the nervous and cardiovascular systems, the gastrointestinal tract, affect reproductive function, the functioning of the mammary and sex glands, and much more.

To find out if everything is in order with your thyroid gland, you need to take just one test – TSH (thyroid stimulating hormone). It is he who controls the thyroid gland, therefore he is called regulating. It stimulates the synthesis of other hormones – triiodothyronine (T3) and thyroxine (T4).

The content of TSH in the blood can fluctuate depending on the time of day: at 2-4 am the level of this hormone is very high, while the minimum level occurs around 17-18 pm.

To get an accurate picture, the TSH test should be taken in the morning on an empty stomach. On the eve, you should stop smoking, drinking alcohol, eating a lot of food, and you should also avoid physical and emotional overload.

If the TSH is normal, the gland is working well. If its level is elevated, it means that the thyroid gland has malfunctioned – hypothyroidism or hyperthyroidism.

Hypothyroidism is the most common disease and dysfunction of the thyroid gland. The reason for this is the lack of iodine in the body. The inability of the thyroid to produce enough hormones (T4 and T3) is the most common cause of hypothyroidism, referred to as primary hypothyroidism. Secondary hypothyroidism is much less common.

Table of thyroid hormones.

Chilliness

Some symptoms of hypothyroidism can develop so slowly that the disease can go on for a long time without being diagnosed.

Low TSH can also be caused by diet, stress, inflammation of the pituitary gland.

Signs of an increase in the concentration of “thyroid gland” hormones – hyperthyroidism or thyrotoxicosis:

• Distracted attention, anxiety, insomnia

• High blood pressure and pulse

• Weight loss with good appetite

• Hair loss

• Heart palpitations

• Shortness of breath

Imbalance of TSH and other important hormones can seriously affect a person’s life. It needs to be kept in order. Check your hormone levels at least once a year as a preventive measure, even when there is nothing to worry about. After all, it is better to prevent an ailment in advance than to treat the disease itself.

Medical Center “Sanas” – qualified doctors of the highest category who know their business “from and to”, a reasonable approach to treatment, only the latest European equipment and the convenience of the location of medical centers in different areas.