TSH is elevated during pregnancy: signs and danger to the fetus

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TSH tests during pregnancy

It is important to take a hormone test correctly to obtain reliable results. Many women use only the simple rule “All blood tests are on an empty stomach”

However, this is precisely what allows them to later be treated for a completely different disease.

The procedure for preparing for the analysis:

For 3 days you need to stop drinking alcoholic beverages, smoking and any physical activity. But this only applies to women who are at the planning stage of pregnancy, since the expectant mother is unlikely to have such habits. Blood is drawn only in the morning and on an empty stomach.

You can’t even drink tea, water or brush your teeth. In order to see how the hormone level changes, it is important to take blood samples for analysis at the same time, minute after minute.

Endocrinologist's recommendations

To find out the true reason for deviations in the level of thyroid-stimulating hormone from normal levels of 3.5, you should contact an endocrinologist. Having taken a blood test for TSH, the doctor, based on this, will issue a referral for an ultrasound of the thyroid gland and conduct additional examination.

If TSH exceeds the norm during pregnancy, then women are prescribed the drug Levothyroxine, which contains an artificial analogue of the T4 hormone. This drug allows you to reduce the production of thyrotropin, bringing it back to normal.

If in the 2nd and 3rd trimesters there is a decrease in thyrotropin levels, drugs are prescribed that suppress the production of thyroid hormones by the thyroid gland. Other measures can also be taken to maintain hormones at the proper level.

In some cases, pregnant women may be indicated for surgical intervention, which allows them to maintain pregnancy and eliminate consequences in the form of congenital thyrotoxicosis in the baby.

It should be noted that a TSH test can be prescribed to women in order to find out how much glucose is absorbed in their body. This test can detect gestational diabetes. This disease usually goes away on its own after childbirth. However, during pregnancy, such women should be under constant supervision of an endocrinologist.

Danger and symptoms of depression

A pathological decrease in thyrotropin is rare, because the standards for the first (1) trimester range from 0.1 mU/l. TSH levels are considered low if the hormone is not detected in the blood. The most common cause of a decrease in thyroid-stimulating hormone during pregnancy is considered multiple births; less often, this occurs with uncontrolled use of iodine preparations.

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Symptoms of deviation will be as follows:

• heartbeat;
• high excitability;
• poor weight gain with normal or increased nutrition.

In some ladies in an interesting position, hyperthyroidism is accompanied by signs of bulging eyes.

A lack of thyroid hormones before the 18th week of gestation is dangerous:

• disruption of the formation of the nervous system (often such newborns are diagnosed with irreversible malformations of the brain);
• miscarriage.

The results of the study are interpreted by an endocrinologist. Treatment is prescribed only after identifying the causes and determining the severity of the abnormalities that have arisen.

Hormones that normalize metabolism

For a pregnant woman, it is very important to eat well, eat properly, and consume all vitamins and minerals. But this may make absolutely no sense if the metabolism is low and everything you need is not absorbed and digested

When the digestive system is weak and the thyroid gland stops producing important hormones, this is what happens. To make sure that everything is in order, you can do a test - the TSH should be normal during pregnancy.

Such an examination is carried out on women long before conception to find out if there are any abnormalities in the functioning of the thyroid gland. If problems are identified, they need to be healed. Of course, they will not affect the fact of conception in any way - they will not prevent the child from being born in the mother’s body. But during its growth and development, great troubles and developmental delays may arise.

At the same time, the problem often arises during pregnancy. The thyroid gland can be quite weak; an unprepared endocrine system will not be able to take care of two living beings at once, so the TSH test will show a serious deviation.

What it is?

TSH is a special hormone called thyroid-stimulating hormone. It is produced by the anterior pituitary gland to stabilize the thyroid gland. It is what creates growth hormone, also known as T4. The action occurs on the principle of supplementation - if the thyroid gland does not produce enough T4, the pituitary gland produces a little more TSH, so that it, in turn, stabilizes the action of the thyroid gland. Similarly, on the contrary - if there is too much T4, stimulation is not needed, the amount of thyrotropin is sharply reduced as unnecessary. Their number is inversely proportional to each other.

These two hormones are extremely important in the body. They affect:

• Digestive system
• Cardiovascular system
• Reproductive system

At the same time, thanks to them, substances such as proteins, carbohydrates, and fats are absorbed into the blood. Both deficiency and excess will be harmful to the body of the mother and child.

Impact and Consequences

Since this hormone itself is not very important - it affects not the body, but only the thyroid gland, its level really needs to be known. As already mentioned, it is inversely proportional to the amount of T4. The more TTG, the less T4, and vice versa. At the same time, it is difficult to directly calculate the level of growth hormone in the body - such a test is complex and not accurate enough. Therefore, checking ttg is much easier and more effective.

In the first weeks of pregnancy, these hormones have a strong influence on the fetus - under their influence, its personal endocrine system develops and the thyroid gland is formed. Due to a lack of T4, developmental delays or undesirable pathologies may occur. In any case, deviations from the norm do not threaten anything good for the baby.

Norm

The usual TSH level is 0.4-4.0 mU/l. In a woman before pregnancy, it fluctuates around 2-3 mU/l. However, after conception, another organism will appear in the woman, which completely changes the picture.

The fact is that at about the 10th week the baby develops its own thyroid gland, but the TSH is not yet formed. But it is necessary to stabilize the level of hormones in it. Since the placenta does not allow TSH to pass through, the required amount of T4 is transferred to the baby from the mother. Thus, in the middle of the 1st trimester, growth hormone in a woman’s body rises sharply, while TSH drops significantly.

Somewhere around the 20th week, the baby begins to secrete its own TSH, so thyroid hormones stop flowing from woman to child. So the T4 level drops - there is no longer a need to provide for both of them, and TTG begins to gradually increase. Therefore, the higher the gestational age, the higher the number the test should show. By the time of birth, the result should stabilize and be equal to normal, as before conception.

However, do not be afraid of a low indicator if you see a small number on the result. Several factors influence the result. For example, during a multiple pregnancy, the TSH level is much lower than during a singleton pregnancy. At the same time, different laboratories conduct different tests: they differ in the sensitivity of their testing systems. The normal level is always indicated on the result in a note. If you are not sure whether your indicator is good or not, contact your doctor - he will decipher everything for you.

Low rate

If your test shows low TSH levels, it means your thyroid gland is producing too much hormone. This disease is called hypothyroidism - it is very dangerous for the child, as it can cause the same disease in the fetus. It can be detected without special tests for TTG; there are some signs for this:

Heartbeat too strong

Oocyte fertilization and thyrotropin levels

Is it possible to get pregnant with elevated TSH?

An increase in TSH value indicates not only diseases of the pituitary gland and thyroid gland. Its level temporarily increases after:

• severe stress;
• asymptomatic microinfarction;
• traumatic contusion of the chest.

It fluctuates in chronic kidney or liver diseases, and some mental illnesses. Long-term disruption of sleep patterns may also be responsible for disrupting the normal rhythm of thyrotropin secretion.

If the elevated TSH level does not have time to affect the full development of the egg and its ovulation, then pregnancy is quite possible.

Immediately after the fertilized egg begins to divide, human chorionic gonadotropin (hCG) begins to be secreted, which causes the thyroid gland to work in an enhanced mode - 1.5 or 2 times more than normal. As a result, a sharply increased synthesis of T3 and T4 very quickly lowers TSH levels.

It is not the TSH level that prevents pregnancy, but diseases that inhibit fertility and cause infertility:

• manifest hypothyroidism – TSH high + T4 low;
• hyperprolactinemia – increased levels of prolactin (another pituitary hormone).

The subclinical form of hypothyroidism (TSH is elevated, T3 and T4 are normal) is not an obstacle to pregnancy.

However, it should be remembered that even in the absence of diseases, long-term elevated TSH will lead to low T3 and T4, which will negatively affect metabolic processes and the functioning of the ovaries: the maturation of follicles with eggs will be disrupted and the development of the corpus luteum will be inhibited, thereby creating problems with conception.

What should TSH be during pregnancy?

As mentioned above, each trimester has its own indicators of hormonal activity.

In 1st trimester

In the first trimester, the permissible level is significantly lower than the standard - 0.1 - 2.5 mU/l. If the expectant mother carries more than one child, the hormone value tends to zero. And as we have already said, this is a completely normal phenomenon, there is nothing to be afraid of. An increase in indicators should begin by the end of the 1st trimester, during the period when the thyroid gland develops in the embryo.

During the first ten weeks of development, the baby receives THC from the mother. And if she had a deficiency or excess of them before conception, then there may be a disruption in the process of formation of all the organs and systems of the child.

In the 2nd trimester

In the second trimester, the fetal thyroid gland starts working. The woman begins a gradual growth of theriotrope, which continues throughout pregnancy.

Despite the fact that by 15-16 weeks the baby produces its own hormone, full functioning of the mother’s thyroid gland is necessary for its development. The norm increases from 0.2 to 3.0 mIU/l. In addition, the level of the T4 hormone also increases.

In the 3rd trimester

By the third trimester, the norm continues to rise to 0.3 - 3.0 mU/l, and T4 returns to normal. By this time, the child becomes independent in providing himself with hormones. By the end of pregnancy, the mother’s hormonal background returns to its original state, the same as it was before conception.

TSH values ​​in pregnant women at different stages - norm and deviations

In a healthy adult, the level of thyroid-stimulating hormone ranges from 0.4–4.0 mIU/l, where IU is an international unit used in pharmacology to measure the dose of substances based on their biological activity; Moreover, the amount of substance in one IU is different for vitamins, hormones, and vaccines.

In pregnant women, TSH norms differ slightly from the standard ones: from month to month, the hormone level jumps from 0.1 mIU/l to 3.5 mIU/l.

In different countries, women who are carrying a child have their own normal values ​​of thyrotropin; Thus, in the USA they are somewhat lower than in Russia.

Doctors are guided by a table of TSH indicators by trimester. So in Russia:

• in the 1st trimester, values ​​from 0.1 mIU/l to 0.4 mIU/l are considered normal;
• in the 2nd trimester, the normal limits expand - from 0.3 mIU/l to 2.8 mIU/l;
• The range of values ​​in the 3rd trimester is even greater - from 0.4 mIU/l to 3.5 mIU/l.

A woman just planning to conceive a child should see a figure of at least 1.5 mIU/l on the certificate with the TSH test results - then most likely there will be no problems with the thyroid gland during pregnancy.

What happens to TSH in the 1st trimester

As a result of fertilization, a zygote is formed - a cell that contains a complete double set of chromosomes; through the fallopian tubes, a new cell, continuously dividing, enters the uterus and attaches to the wall of the organ - this is already an embryo. The zygote path is accompanied by increased production of hCG (human chorionic gonadotropin), one of the most important pregnancy hormones.

HCG causes the thyroid gland to increase the synthesis of the hormones T3 and T4; at the same time, the size of the gland itself grows by half. In the bloodstream, the concentration of both thyroid hormones increases, which ultimately block the pituitary gland receptors, so that the synthesis of TSH, on the contrary, slows down. The level of thyrotropin drops, sometimes to a minimum value of 0.1 mIU/l. These numbers are typical for 10–12 weeks of pregnancy.

When an expectant mother is carrying two or more babies, the hCG level jumps so much that the finally suppressed TSH drops almost to zero - but in the 1st trimester, and even during a multiple pregnancy, this indicator is not dangerous.

TSH does not reach the fetus - unlike T4; and thyroxine is exactly what a baby needs, since his own thyroid gland has not yet formed. The hormone will help the unborn child develop within normal limits.

After the 10th week of pregnancy - the peak of hCG activity - the level of the hormone gradually drops.

Thyroid-stimulating hormone in the 2nd and 3rd trimesters

By the beginning of the 2nd trimester, the amount of hCG decreases significantly; TSH finally receives favorable conditions for synthesis. In addition, estrogen begins to grow, which in turn increases the production of proteins that bind the T3 and T4 hormones in the bloodstream. This stimulates the pituitary gland to produce additional TSH.

Meanwhile, from the 15th week the unborn child produces its own thyrotropin, and by the 18th week the fetus has a full-fledged thyroid gland. A placental barrier is also formed, which can now protect the baby from some of the mother’s aggressive hormones that threaten toxic infection.

By the 3rd trimester, the TSH level is steadily increasing - within normal limits in a healthy woman - and approaches standard levels for an adult.

Treatment of high and low TSH

Many pregnant women do not particularly focus their attention on such pathologies, believing that these are just hormones that will return to normal during childbirth. They self-medicate by taking other hormones or vitamins, but they themselves do not understand that they are harming themselves and their unborn child

The diagnosis can only be made by a specialist after a blood test for hormones. No initial examination will provide accurate indicators for diagnosis.

It is important to remember that all hormones from the mother go to the baby and only the mother decides what defects he may be born with by self-medicating

If previously there were no drugs that supported the normal state of hormonal levels, now they appear every year in large quantities. Modern medicine has long developed drugs that can increase or decrease the level of TSH in the blood.

1. When TSH rises, hyperthyroidism begins to develop. As a therapeutic therapy, a special drug is prescribed - thyroxine (synthetic T4 hormone). Only a doctor can select the dosage, taking into account the woman’s age, pregnancy and other concomitant diseases. You should take thyroxine constantly, regularly checking the level of the hormone in the blood.
2. If the TSH hormone decreases during pregnancy, the woman develops hypothyroidism. To eliminate the symptoms of the disease, women are prescribed drugs that have a special form.

The treatment regimen is prescribed only by the doctor individually for each patient.

Often, for hyperthyroidism, a drug such as Eutirox is prescribed. This is a synthetic T4 hormone. The doctor prescribes the appropriate dosage of the drug. However, you should adhere to the following rule: gradually increasing the dose. Many specialists prescribe incorrect doses to patients. In such cases, the process of lowering the level develops very quickly, but this leads to the development of other diseases, such as tachycardia, arrhythmia. The heart begins to work faster, and due to unusual work, a rhythm disturbance may occur. With any physical activity, a woman may feel constant shortness of breath, tremors of the arms and legs, poor sleep and rapid heartbeat even during sleep. In such cases, you should temporarily stop taking the drug and seek help from a doctor. The specialist will select the correct dosage and prescribe treatment according to a new regimen. Don't be afraid to talk about your warning signs. After all, the entire course of effective and rapid treatment depends on this.

Every woman should take care of her health. Not because she is expecting a child, plans, but because she is a mother now or in the future tense. Her health directly affects the proper development of the baby.

Hormonal levels are easily disrupted by even the slightest excitement, a surge of emotions at work, a hard day, and it is easier to monitor its condition and correct timely deviations from the norm than to be treated for more serious diseases.

Moreover, the TSH level can never be brought back to normal permanently. Only by constantly supporting it with special medications or taking vitamins can you achieve normal functioning of a healthy body.

What to do if you have hormonal imbalances

Fear for the fate of the unborn baby haunts almost all women in an interesting position, so they perceive any deviations as a threat. If low or high TSH is detected during pregnancy, you should not immediately panic: modern developments in medicine make it possible to correct hormonal levels, preventing dangerous consequences.

First of all, the woman will be prescribed a more complete examination:

• determination of general hormonal levels (levels of T3, T4, free thyroxine, etc.);
• detection of antibodies to thyrotropin (an increase in antibody titer will indicate hyperthyroidism, and low results will indicate hypothyroidism).

To reduce the risk of receiving an unreliable result, a woman is recommended 3 days before visiting the laboratory:

• Avoid foods containing iodine (seafood, iodized salt);
• do not take iodine-containing medications;
• give up alcohol.

In the morning, when you donate biological fluid, you need to avoid any physical activity and do not smoke. Failure to comply with the rules often becomes the cause of an increased (less often - decreased) TSH level.

Eating in the morning is not prohibited, but it is recommended to refrain from eating.

Another reason for concern for expectant mothers is how many days the TSH blood test is done. Many pregnant women think that even one day of delay is dangerous for the baby.

First of all, about the timing of the study: it will range from 2 days to a week. Private clinics or emergency laboratories will provide test results faster.

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While waiting, many pregnant women manage to find information on various websites about what TSH levels are during pregnancy and become familiar with the dangerous consequences of hormonal disorders. In fact, there is no serious cause for concern. If a woman in an interesting situation is regularly examined by a doctor, then TSH deviations from the norm in women during pregnancy will be insignificant, which means they will not cause much harm to the fetus.

Depending on the nature and causes of the abnormalities that arise in hypothyroidism, the following are prescribed:

• medicines with iodine;
• hormone replacement therapy (L-thyroxine).

To treat hyperfunction of the thyroid gland, drugs are used that inhibit the functional activity of the organ. The prescribed medication should be as safe as possible for the baby.

Additional laboratory tests are necessary to determine the nature and cause of possible violations. This information will help the endocrinologist select effective, safe therapy.

What does low TSH indicate during pregnancy?

During pregnancy, low TSH is normal, especially in the early stages, but it can also indicate increased thyroid function - thyrotoxicosis. Less common is a decrease due to diseases of the pituitary gland and hypothalamus due to injuries, inflammation, brain tumors, and vascular disorders.

Symptoms of decreased hormone levels

A decrease in the level of thyroid-stimulating hormone of the pituitary gland manifests symptoms only with increased thyroid function. It produces thyroxine in excess quantities. When its level increases, women complain of:

• weak weight gain as pregnancy progresses;
• sweating;
• intolerance to heat and stuffiness;
• increased appetite;
• hand trembling;
• strong and frequent heartbeat, pulsation in the head, neck, stomach;
• nausea, vomiting, diarrhea;
• rise in body temperature without signs of infection.

Pregnant women become very impressionable and tearful, and sleep is disturbed. Possible protrusion of the eyes, lacrimation, pain when looking at a light source, double contours of objects.

Elevated TSH levels

If a high level of thyroid-stimulating hormone is detected, this indicates the presence of problems in the thyroid gland, but may be associated with an unstable psycho-emotional state of the woman. Other reasons for increased TSH in pregnant women include:

• inflammatory processes occurring in the thyroid gland;
• gestosis;
• the presence of a benign or malignant tumor in the pituitary gland;
• disruption of the adrenal glands;
• uncontrolled use of iodine-containing drugs in high dosages;
• lead poisoning;
• consequences after removal of the gallbladder and others

Symptoms with elevated levels of thyrotropin manifest themselves in many ways.:

• excess weight appears, which is usually difficult to lose;
• pregnant women note a slight thickening of the neck;
• causeless fatigue appears, loss of strength and decreased ability to work are observed;
• a depressive state develops;
• there is a decrease in intellectual abilities. The woman becomes inattentive, absent-minded, her memory deteriorates;
• the pregnant woman notes increased irritability and nervousness;
• Various sleep disorders are observed. For example, a woman cannot sleep for a long time, often wakes up, etc.;
• a pregnant woman's appetite decreases significantly and taste preferences change;
• Nausea is very common;
• when measuring body temperature, reduced values ​​can be noted;
• pallor of the skin is observed;
• swelling develops;
• tachycardia and other alarming symptoms appear.

The role of TSH in the body in pregnant women

The hormone is formed in the pituitary gland and regulates the functioning of the thyroid gland. It is the most important in the entire metabolic system.

Thyrotrope helps the work of other important hormones - triiodothyronine (T3) and thyroxine (T4). Thanks to the coordinated work of these three, the energy balance remains normal, protein and vitamin A are synthesized, intestinal motor function and the vital activity of the central nervous system are regulated. Active hormones preserve our vision, hearing, heart and blood vessels.

All of them are closely related to each other - thyroid hormone helps the production of T3 and T4, but if their level is exceeded, they are able to suppress it. When the body does not produce enough of these elements, the thyroid gland begins to grow.

Accordingly, the indicator changes throughout pregnancy. At the very beginning, when the embryo cannot yet create anything on its own, it borrows them from the mother. The fetus develops and develops its own thyroid gland, and the pregnant woman’s TSH is restored. It turns out that the indicators vary over nine months. But with significant deviations from the initial values, a risk for the normal development of the child appears.

TSH value

TSH—thyroid-stimulating hormone—is a substance produced in the pituitary gland that affects the functioning of the thyroid gland. Also, thanks to TSH, very important hormones are produced: T3 (triiodothyronine) and T4 (thyroxine), which in turn are responsible for metabolic processes: fats, carbohydrates, proteins, regulates the functioning of the reproductive, nervous and cardiovascular systems, for the functioning of the gastrointestinal tract (gastrointestinal -intestinal tract), take part in the formation of glucose and other vital substances. The thyroid gland, in turn, is responsible for:

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• restoration of bone tissue processes;
• normalization of hormonal levels;
• control of metabolism and chemical reactions;
• regulation of calcium levels, as the main biomaterial for bone marrow;
• control of cell division in the body

Symptoms of high TSH

If TSH levels are 2.5 times or more above normal, this is especially dangerous in the first 12 weeks.

Manifestations and symptoms:

• slowness of reactions;
• lethargy;
• absent-mindedness;
• irritability;
• neck deformities;
• decreased appetite up to its complete absence;
• symptoms of constant nausea combined with steady weight gain;
• constant constipation;
• temperature is below normal;
• There are also symptoms of skin changes: it is dry and pale;
• hair fall out;
• brittle nails;
• tendency to swelling on the body and face;
• the appearance of fatigue and weakness in the morning;
• daytime sleepiness and insomnia at night.

Many signs may resemble early toxicosis, so it is better to find out the causes of the condition from a doctor. But more often the symptoms do not attract attention, because in the CIS the Chernobyl accident still resonates and chronic iodine deficiency is noted.

A high TSH level should not cause panic, because it is easy to correct conservatively. But high TSH indicates the onset of goiter or thyroiditis. The decision about tests is made by the doctor. If a thyroidectomy was performed before conception, hormones are taken throughout pregnancy.

What conditions can thyroid gland have?

1. Eutheriosis – the functioning of the gland is normal.
2. Thyrotoxicosis – not only a decrease in TSH is noted, but also an excess of thyroid hormones and poisoning by them. This is Graves' disease.
3. Hyperthyroidism is an excess of hormones without intoxication.
4. Hypothyroidism is a lack of T3 and T4 during pregnancy.

The role of the hormone and the danger from its excess

Thyroid-stimulating hormone is a substance synthesized in a brain structure called the pituitary gland. The main and only task of this biologically active compound is to control the level of hormones produced by the thyroid gland.

The thyroid gland provides the human body with two main substances: T3 and T4. Both of these compounds affect many processes, ranging from metabolism to the functioning of all organs and systems.

It mainly depends on the level of TSH whether T4 will be normal, since it is this compound that its main action is directed to. T4 acts as a prohormone, that is, a substance with low biological activity. Only after it is released into the blood does it transform into T3, which has an activity tens of times greater than T4.

If a woman becomes pregnant, a very high TSH can lead to abnormal pregnancy and affect the baby. First of all, the child’s psyche and mental development are under attack.

In the first trimester, high levels of thyrotropin are especially dangerous. This is explained by the fact that the fetus does not yet have its own thyroid gland; it is forced to perceive all the hormones coming from the mother’s bloodstream. Also during this period, there is an active formation of vital organs and systems, which can be negatively affected by excess TSH.

A decrease in thyroid function in a woman with a simultaneous increase in TSH levels may indicate a number of pathologies that can result in termination of pregnancy. These include:

• preeclampsia (another name is severe gestosis);
• hemodialysis;
• insufficient functioning of the adrenal glands;
• diseases of a tumor nature;
• mental disorders, etc.

The consequences for a child if high TSH levels are ignored may be as follows:

• development of congenital hypothyroidism;
• development of congenital hyperthyroidism;
• mental retardation;
• development of mental illness, etc.

Thyroid-stimulating hormone (TSH) – in “waiting for a miracle” mode

The problem of thyroid pathology in our country is extremely relevant. According to some data, every third resident of our state has problems with the thyroid gland, according to others - almost every second, and most importantly - most of them are women. And according to the results of a study by domestic scientists, slightly less than half of pregnant women have one or another thyroid disease. This article will tell you what the level of thyroid hormones and TSH should be during pregnancy.

Let me introduce myself: the thyroid gland

The thyroid gland is an organ that produces hormones responsible for regulating almost all metabolic processes in the body. The thyroid gland is located in the neck and consists of three parts: two lobes and an isthmus. There are two iodine-containing thyroid hormones - thyroxine (T4) and the more active triiodothyronine (T3), these hormones are also called thyroid hormones. The amount of these biologically active substances is regulated by the brain, or more precisely by its part - the pituitary gland, which can also produce various hormones, in particular thyrotropin or TSH. This hormone has the ability, if necessary, to enhance the functioning of the thyroid gland and thereby increase the concentration of thyroid hormones in the circulatory system.

The thyroid gland and the beginning of a new life

Pregnancy is always a special kind of stress for a woman’s body, as a serious reconfiguration of all organs and systems occurs due to changes in hormonal levels. From the moment it attaches to the wall of the uterus, the embryo begins to secrete a special hormone into the maternal blood - human chorionic gonadotropin, or hCG for short. This hormone has various effects on the body of a pregnant woman, but among other things, it has an effect on the thyroid gland similar to that of thyroid-stimulating pituitary hormone.

Since the embryo in the early stages is not yet able to independently produce thyroid hormones, due to its lack of one, it receives them from the mother’s blood. High levels of hCG stimulate the activity of the thyroid gland, and it begins to release more thyroxine. An increase in T4 and T3 leads to inhibition of TSH production by the pituitary gland during early pregnancy.

Since the period of maximum production of chorionic gonadotropin is the first trimester, low TSH during pregnancy can be recorded at this time.

By the beginning of the second trimester, the fetus already has its own thyroid gland, which, however, is only “learning” to work and therefore is not able to cover the needs of the growing body on its own.

• In every fifth pregnant woman, the TSH level in the first trimester decreases so much that it may not be detected by some laboratory test systems.
• At 10-11 weeks, fetal thyroid cells are only capable of capturing iodine from the bloodstream.
• At the 15th week of development, the first hormones begin to be produced in the fetal thyroid gland.

With a decrease in the concentration of hCG in the mother’s blood, from the second trimester of pregnancy TSH begins to increase to the initial level and subsequently its indicators during a normal pregnancy remain within acceptable limits.

Normal TSH limits for adultsNormal

When to donate blood for TSH

As you can see, thyroid-stimulating hormone has one of the key influences when carrying a healthy baby. It is best to get tested for its content when planning conception. The norm is considered to be between 0.4-4.0 mU/l. If deviations are found, you need to understand them well.

Take an additional test for the presence of antibodies to TPO. An increase in their level often indicates that any disease during pregnancy can be activated. But don't panic if your results don't match the norm. Modern medical means and a competent specialist will help bring your hormonal balance back to normal and provide favorable conditions for the development of the fetus.

In pregnant women, TSH levels are determined at 6, 7, 8, 9 weeks, in order to identify thyroid dysfunction at an early stage. If your results are normal, the next tests should be taken in the second and third trimester (at 20 weeks or later). If something is wrong, your doctor will check you more often.

Symptoms of elevated TSH

TSH levels affect the functioning of many body systems. A change in its indicators affects the general well-being of the pregnant woman. Some symptoms of increased thyroid-stimulating hormone are quite difficult to distinguish from the first manifestations of pregnancy in the early stages.

These are:

• weakness;
• feeling of slight malaise;
• high fatigue;
• decreased physical activity;
• slow thinking;
• decreased body temperature;
• apathy;
• absentmindedness;
• loss of appetite.

All these phenomena can be observed in a woman in the early stages due to a general change in hormonal levels. This is why many pregnant women often do not realize that their TSH levels are abnormal before taking tests.

However, there are some distinctive signs indicating increased levels of the hormone. They can be observed with a significant deviation of TSH from the norm. It is in these cases that there are risks for the mother and fetus.

A pregnant woman experiences a slight lump in the neck area. It appears due to an increase in the volume of the thyroid gland. Such changes occur due to the fact that the organ cannot cope with the normal production of the hormones T3 and T4. Also, due to general changes in hormonal levels, a pregnant woman experiences a significant weight gain. In the first trimester, a woman should gain only a few kilograms. If the weight gain is more than 6 kilograms, then this is quite an alarming signal.

If a pregnant woman detects one or more of the described symptoms, in combination with elevated TSH, additional studies are carried out and the necessary treatment is prescribed.

An increase in TSH is quite common in pregnant women. It can be either normal or pathological. Only the attending physician can make a correct diagnosis based on the analysis data and prescribe appropriate treatment.

During pregnancy, a restructuring of a woman's entire hormonal system occurs, including the endocrine system. Therefore, it is important to monitor your thyroid hormone levels. The TSH norm during pregnancy by trimester and symptoms of deviations - this is the subject of the next article.

What are the reasons for the increase in thyroid hormone, we will consider in this material.

What is the level?

TSH norms are precisely prescribed, since thyroid hormones are irreplaceable. They participate in the process of metabolism (metabolism) in the girl’s body.

Their role in ensuring mental functions, maintaining the reproductive system, and gastrointestinal tract has been proven. They affect the functioning of the heart and blood vessels.

The norm of T4 and T3 is regulated by TSH. This control is carried out using the feedback principle. When there is insufficient content of these substances in the body, the brain sends signals and more TSH is produced.

Under its influence, T3 and T4 are diligently produced. When their content returns to normal, they begin to suppress the production of TSH.

But in some conditions this pattern is changed. During pregnancy, the entire hormonal level of the body is increased.

A variant of the norm is the normal regulation of hormone concentrations. But there are various pathological conditions in which such interdependence is sharply disrupted. The following ailments develop:

• hyperthyroidism - pathologically increased levels of T4 and T3 in the body;
• hypothyroidism - decreased concentration of thyroid hormones;
• thyrotoxicosis - analysis shows excessively active formation of the hormones T4 and T3, which poisons the body.

The normal content of gland hormones (T4, T3), its full functioning is called euthyroidism. Every person should control their health.

Hormones during pregnancy ensure its normal course. If hormonal levels are disrupted, there may be threats of interruption.

One episode of impaired concentration of substances does not indicate the presence of an illness. To confirm the pathology, repeat tests, additional tests and other examinations are prescribed.

How substances are regulated

Hormonal homeostasis is controlled by TSH receptors. These are special structures that respond to the hormone and stimulate the level of T3, T4 that it should be.

Such receptors are responsible for the hormones of the gland, and therefore are located directly in it.

In the second trimester, immune regulation often fails. When the immune system is disrupted, antibodies to such receptors are produced. Thyroid-stimulating hormone loses its power over gland hormones.

There are 3 types of antibodies:

1. Structures that directly affect TSH activity. Stimulation of the thyroid gland is blocked. Its cells do not respond to TSH, which is why the metabolism is disrupted, the concentration begins to decrease, and an adverse effect on conception is observed.
2. Antibodies that block the functioning of receptors and imitate the effect of the hormone on the organ. This causes pseudostimulation of the gland. The production of T3 and T4 increases uncontrollably in the body, which adversely affects conception. They occur in all three periods of pregnancy.
3. Antibodies that bind tightly to receptors and prevent the hormone from affecting them. Such elements are found in the third month of pregnancy.

What is the danger of antibodies for a child? The first trimester is the most important period of the entire pregnancy. During it, the birth of all organs and systems occurs.

Violation of the maternal hormonal background provokes a malfunction of the fetal body. During pregnancy, the consequences of an antibody attack can be unpredictable.

Antibodies easily penetrate the placenta, adversely affecting the development of the fetus. What result? He develops damage to the thyroid gland in utero.

The 3rd trimester is considered the most unfavorable, when a deficiency of organ hormones causes a delay in neuropsychic development.

Therefore, all pregnant women (in the presence of gland pathology) are required to undergo tests for antibodies to receptors. This allows us to identify the risk of glandular damage in a child.

What is TSH and its role during pregnancy

The body develops under the influence of hormones - groups of biologically active substances that are formed in the endocrine glands, as well as in the kidneys, stomach, intestines and other organs. From the place of synthesis, hormones are carried by the blood and regulate biochemical processes in vital systems. It is curious that there are very few hormones in the blood, but these substances, without exaggeration, control the body.

TSH, thyroid-stimulating hormone (another name is thyrotropin), is produced in the anterior lobe of the appendage of the brain - the pituitary gland. The main task of TSH is to control the functioning of the thyroid gland. This butterfly-shaped endocrine gland is located under the larynx and serves as a reservoir for storing iodine.

The size of the thyroid gland is modest - two by four centimeters - but the gland plays a vital role in the functioning of the human body

What happens is this: thyrotropin binds to certain receptors on the surface of the thyroid gland and stimulates the production of two iodine-containing hormones of the gland - T4 (thyroxine) and T3 (triiodothyronine). As a result, all three hormones are responsible in the body for:

• proper metabolism;
• synthesis of nucleic acids, as well as erythrocytes - red blood cells;
• glucose production;
• work of the heart and blood vessels;
• transmission of impulses between neurons in the brain;
• respiratory system support;
• normal functioning of the digestive tract;
• coordinated functioning of the genitourinary system;
• mental condition.

The mutual influence of the three hormones is sometimes called a “swing”: the more TSH is produced, the less T4 and T3 become - and vice versa. The reason is that TSH stimulates the production of two other thyroid hormones until their high levels begin to inhibit the production of TSH itself in the pituitary gland. But gradually thyroxine and triiodothyronine are absorbed in the tissues, the level of both decreases again - which means the secretion of thyrotropin is restored.

It is enough to measure the amount of TSH in the body to find out whether the thyroid gland is in order or not, what pathologies are present.

An analysis of the level of thyroid-stimulating hormone in the blood is prescribed to every expectant mother who is registered at the antenatal clinic. If a woman has been diagnosed with thyroid-related complications during previous pregnancies, TSH levels should be carefully monitored before becoming pregnant again.

Too high or too low hormone production signals that the endocrine system is stalling. This condition triggers negative and often irreversible processes in the body; this leads to health problems, and in severe cases, fetal death. The main consequences are:

• pathologies of the nervous system of the unborn child;
• gestosis or late toxicosis in the mother, which threatens the death of the fetus in the womb; sometimes the woman herself falls into a coma (eclampsia) and dies;
• placental abruption - if the temporary organ formed in the 2nd trimester detaches more than half, the fetus will die;
• intrauterine growth retardation; as a result, the child is at risk of mental retardation after birth;
• miscarriage;
• the birth of a baby with thyroid pathology.

If a woman is trying unsuccessfully to become pregnant, a TSH test is also prescribed; Disturbances in the functioning of the endocrine system provoke abnormal metabolism in the ovaries. In this case, a pelvic ultrasound will detect a lack of egg and follicle, as well as insufficient development of the corpus luteum (the temporary gland that synthesizes the “pregnancy hormone” progesterone).

Possible reasons for TSH fluctuations

Hormones have a great influence on the course of the entire pregnancy and the development of the child, so it is worth paying close attention to changes in TSH, both its deficiency and excess. These disorders can cause irreparable consequences: miscarriage, placental abruption, malformations and impaired fetal growth, premature birth.

We already know that in the first trimester the thyroid hormone level is reduced. But still, an experienced endocrinologist should help you figure out whether this fall is associated with physiological processes or pathological ones. The latter may indicate serious illness.

Reasons for increasing hormone levels

During the period of bearing a child, the level of thyrotropin is under the control of the hypothalamus, which produces a biologically active substance that acts on the pituitary gland and increases the level of TSH. All elements of the hypothalamus-pituitary-thyroid system are closely related to each other.

Most often, the hypothalamus begins to actively produce TRH, which acts on the pituitary gland, if a woman has weakened thyroid function. In this way, the body tries to force the organ to function correctly and produce a sufficient amount of hormones necessary for the woman herself and the full course of her pregnancy.

During pregnancy, a slight increase in TSH is allowed and is considered normal only at first, since the female body has not yet had time to adapt to its new condition. In the first trimester, a decrease in TSH levels may also be observed, which is also considered a normal variant due to the work of adaptive mechanisms.

The hormone level returns to its biological norm towards the end of pregnancy, and sometimes only after childbirth.

Women should be concerned if, according to tests, the norm is exceeded several times. Minor deviations up or down are physiological.

Alarming symptoms of elevated TSH

What is dangerous about elevated TSH during pregnancy? Normal functioning of the mother's thyroid gland is very important for the development of the child, especially in the first trimester.

It is during this period that all the basic systems of the baby’s body are formed.

In this regard, the TSH test is performed one of the first during pregnancy. This allows you to start the necessary treatment on time.

A significant increase in the hormone level may indicate dangerous changes in the mother’s body and the risk of congenital pathologies in the fetus. A cause for alarm is an excess of the TSH norm by 2.5 - 3 times. Most often, this indicates weakened thyroid function (hypothyroidism). After additional tests, a pregnant woman is usually prescribed treatment in the form of taking synthetic hormones. If hormonal levels are not normalized in time, a high TSH level during pregnancy can lead to problems with the mental and psychological development of the child.

In addition, a deviation of the hormone from the norm may indicate the following health problems in the mother:

• gestosis;
• dysfunction of the adrenal glands;
• pituitary tumor;
• cholecystectomy.

If the TSH level is increased several times during pregnancy, appropriate studies must be prescribed to identify the cause of deviations from the norm.

It is advisable for all pregnant women to undergo hormone tests. Low TSH during pregnancy: reasons for deviation from the norm and what to do with such indicators?

What TSH level in the blood is normal and what an increase or decrease in this value indicates, you will learn in this topic.

Planning a pregnancy is an important step in a woman’s life. At this stage, it is important to undergo basic tests to monitor the condition of the body. An important test is donating blood for TTT. Follow this link https://gormonexpert.ru/zhelezy-vnutrennej-sekrecii/shhitovidnaya-zheleza/ttg-pri-planirovanii-beremennosti.html you will find information about normal hormone values ​​when planning pregnancy, and also find out what to do if there is deviation from the norm.

Consequences for mother and fetus

When TSH is below normal, this is accompanied by negative consequences for the fetus and the pregnant woman:

• early toxicosis with uncontrollable vomiting;
• severe pregnancy;
• risk of early miscarriage, premature birth, cessation of fetal development, stillbirth;
• increased blood pressure;
• heart failure - palpitations, shortness of breath, swelling, enlarged liver;
• placental abruption;
• bleeding in the postpartum period.

Excess thyroid hormones inhibit the formation of the placenta. Malnutrition of the fetus often causes abnormalities in its development, some of which are incompatible with life. Children may be born with low body weight, increased excitability, and delays in physical and mental development.