Synonyms in the broadest sense

Congenital hypothyroidism, cretinism, athyroidism, thyroid dysplasia, thyroid ectopy


The thyroid is a hormone-producing bilobed gland in the front of the neck. The Hypothyroidism is present when the thyroid gland no or just insufficient quantities to the Thyroid hormones Thyroxine and Triiodidthyronin form, so that the hormone effect on the target organs is reduced or absent.
The thyroid hormones cause one Increase in the overall metabolism and a Promote growth and development.


If there is a deficient formation of the hormones produced, one speaks of one Hypothyroidism.
The Boost thyroid hormones our Metabolism and increase the functions of circulation, growth and psyche. An underactive thyroid throttles therefore the physical activity and lets the metabolism run on the back burner.
The hypothyroidism can cause undetected severe physical and mental developmental damage in growing children, which is why in Germany with the Neonatal examination a compulsory test is carried out.

Frequency distribution

The hypothyroidism affects approx 1 % of the population, women are more frequently affected than men.
Congenital hypothyroidism occurs in 1 in 5000 newborns and is one of the most common congenital metabolic diseases.

Thyroid hormones

The thyroid hormones L-tetraiodothyronine (T4), also called thyroxine, and L-triiodothyronine (T3) have various effects and sites of action.
The release of thyroid hormones is controlled via a closed control loop.
The hormone TRH (thyrotropin releasing hormone) is released from the central nervous system and acts on the pituitary gland, which now increasingly produces TSH (thyroid stimulating hormone, thyroid stimulating hormone) and releases it into the blood.
TSH works on the thyroid gland. The thyroid cells are stimulated to produce hormones, so that T3 and T4 are subsequently released.
Outside the thyroid gland, T4 is converted to T3, which is the more active of the two hormones. The release of thyroid hormones into the blood, in turn, as part of a feedback reaction in the control loop, means that less TRH and thus TSH are released. The concentration of the thyroid hormones T3 and T4 in the blood is the basis of this regulatory cycle.


The primary hypothyroidism is the most common cause. This is because of this type of hypothyroidism Problem in the thyroid gland itself. The triggers for this can be either innate or acquired be.
In Germany about one comes from 4000 newborns with an underactive thyroid to the world. In this case, the organ is either completely absent, has developed incorrectly, or the thyroid gland has impaired hormone production due to a genetic defect. Overactive drug therapy for an overactive thyroid in the mother during pregnancy can also trigger an underactive thyroid in the newborn.
The acquired primary hypothyroidism occurs with increasing age and is usually the result of a permanent inflammation of the thyroid tissue. The underlying disease is known as Hashimoto's thyroiditis. This is a Autoimmune disease unclear genesis. In this case, the body produces proteins that are directed against the body's own tissue, so-called antibodies, which mistakenly recognize, attack and destroy the thyroid tissue as foreign. The death of the functional thyroid cells ends in an underactive thyroid.
Another cause of an underactive thyroid can be a complication from medical treatment means Medication, Radiation therapy or surgical fix an overactive thyroid, in which too much of the hormones are produced and the body is constantly running at full speed.
One in our country very much cause that has become rare an underactive thyroid is a Iodine deficiency. In order to synthesize the already mentioned hormones T3 and T4 the thyroid gland needs as Iodine building block. In our latitudes, the trace element iodine is often added to food, so that deficiency symptoms can be avoided through food alone.

Is the cause of the hypothyroidism not in the organ itself, but in the the thyroid superordinate control centers, which are in our brain, we speak of secondary or tertiary hypothyroidism.
Damage to these brain structures can be caused by injuries, tumors, surgery or radiation therapy in the head area. The hormones made in the brain centers are sent from the brain to the thyroid through the bloodstream and normally control the production and distribution of thyroid hormones. A disturbance in their synthesis leads to the defective production of T3 and T4 in the thyroid gland. The result is an underactive thyroid.

Causes of congenital hypothyroidism

We do one with an infant Hypothyroidism diagnosed then this can have various causes. The thyroid gland is not created or not present (athyroidism), the thyroid gland is deficiently developed (thyroid dysplasia) or is not in the physiological, normal anatomical position, which limits its function (thyroid ectopy).
Very rare causes of a congenital hypothyroidism are defective thyroid hormone production or resistance (= insensitivity) of the cells to the hormones, so that they do not respond adequately to the hormonal signals.


The Symptoms of an underactive thyroid can be different and do not always have to appear.
Due to the slowed down metabolic processes, the body runs on the back burner. The typical complaints of one are therefore fatigue and Drop in performance, Gaining weight without changing your eating habits, increased Sensitivity to cold, dry rough skin, Hair loss due to hypofunction, low pulse or constipation.
Externally, an underactive thyroid can lead to the so-called Myxedema to lead. Here it comes to a Swelling of the subcutis by multiple sugar storage in the connective tissue, which leads to swelling can lead anywhere on the body.
In addition, the lipid metabolism can be affected, which increases the risk of vascular calcification with diseases of the cardiovascular system.
In addition, an underactive thyroid can occur too depressed mood, Menstrual irregularities at the woman or at sexual aversion lead in both sexes.
In older patients in particular, the symptoms of an underactive thyroid, such as an increased sensation of cold, decreased performance and depressed mood, are often mistakenly misunderstood as signs of aging.
At Newborns and infants can Sedentary lifestyle, Unwillingness to drink, weakened reflexes, constipation as well as neonatal jaundice that persists beyond the natural condition may be indications of an underactive thyroid.
Acquired hypothyroidism develops insidiously and is often associated with minor symptoms at first. This is why the hypothyroidism is usually only recognized at an advanced stage.

Symptoms of congenital hypothyroidism

During and after birth, the children stand out due to the following unspecific symptoms that are typical of hypothyroidism.
The children with an underactive thyroid are more likely to have one Jaundice affected, which lasts over 14 days (Icterus neonatorum prolongatus).
they have one weak sucking reflex and drink badly, they also show one Sedentary lifestyle and weakened reflexes. There is also one noticeable in many children big tongue (Macroglossia).
The children are often with an underactive thyroid constipation (=Constipation) affected.
The fall in toddler age Growth lag and a reduced height, that tooth - and bone age is inadequate for the age of the child, i.e. for the age of the child are those Underdeveloped teeth and bones.
Those affected show failure to receive adequate treatment mental retardation and in many cases have one decreased intelligence.
The hypothyroidism can also lead to a Hearing loss and as a result to Speech disorders to lead. In addition, in some cases there may be an isolated increase in the second, diastolic blood pressure value (see also: Increase in the second blood pressure value).

Read a lot more information on this topic at: Symptoms of an underactive thyroid

Cretinism - developmental disorder with congenital hypothyroidism

The full screen of a untreated hypothyroidism in children is the cretinismwho as childlike Development failureg is defined, which is caused by the lack of thyroid hormones.
The children are from irreparable damage above all of the central nervous system and their Development is delayed or disturbed. Short fingers, skeletal malformations, open ones Fontanelles or inner ear hearing loss or deafness are possible symptoms of cretinism and occur together.


In order to be able to make the diagnosis of hypothyroidism, your attending physician will have a detailed discussion in advance about your current symptoms and previous family illnesses.
The question of their eating habits will also interest the doctor in order to detect an iodine deficiency due to insufficient iodine intake from food.
The physical examination follows after the so-called anamnesis interview. The examiner stands behind the patient and scans the neck region with both hands. The tactile findings can, for example, provide indications of an enlarged thyroid gland.
If an underactive thyroid is suspected, an ultrasound is performed on the patient lying down. The ultrasound gives information about the size, texture, position and structure of the thyroid gland.
An additional examination as part of the diagnostic work-up of an underactive thyroid gland, so-called scintigraphy can be used. A radioactively marked substance is introduced into the body's circulation through a vein. Normally this substance accumulates in the thyroid tissue and can be represented graphically. In the case of an underactive thyroid, the thyroid absorbs the substance less. This examination method is not a routine in diagnosing hypothyroidism but is used for specific questions.

Hypothyroidism is suspected by a blood test to determine the thyroid values. The so-called TSH value, T3 and T4 are determined. The TSH value, short for thyroid stimulating hormone, is produced in the central nervous system in the pituitary gland and stimulates the thyroid gland to produce hormone via the bloodstream.

In the case of primary hypothyroidism, the TSH value is increased, as the negative feedback mechanism to the brain is missing due to the deficient production of T3 and T4 and the production of TSH is massively stimulated.

In the case of secondary hypothyroidism, the problem lies in the brain, the production site for TSH, which is why the value here is reduced. A normal TSH value largely rules out an underactive thyroid. The thyroid hormones T3 and T4 can still be in the normal range (latent hypothyroidism), in the lower normal range or decreased. In the latter case, it is then referred to as manifest hypothyroidism.
If an acquired Hashimoto thyroiditis is suspected, the thyroglobulin and thyroid peroxidase antibodies are also determined in the blood.

Read more on the topic Hypothyroidism values

In the case of newborns, the mandatory screening is carried out by examining heel blood with subsequent determination of the laboratory values ​​mentioned above.

Hypothyroidism screening in newborns

When required by law Hypothyroidism screening as part of the newborn screening on 2-3. Day of life of the child can be Hypothyroidism can be determined: The concentration of TSH is determined. This hormone causes the release of the thyroid hormones T3 and T4.

A few drops of blood are taken from the newborn's heel between the 36th and 72nd hour of life and dripped onto a special filter paper.
In the case of congenital hypothyroidism, the concentrations of T3 and T4 are reduced because the thyroid does not produce them or does not produce them in sufficient quantities. Due to this under- or under-production of hormones, the TSH value is increased.

A TRH and TSH increase then takes place via the control cycle, the aim of which is to increase thyroid hormone production.
Since the thyroid cannot react to this stimulus, the hormone deficiency situation remains with an increased TSH value.


Hypothyroidism is an incurable disease. Treatment of an underactive thyroid should be started as early as possible in order to avoid permanent long-term damage.
The aim of therapy for hypothyroidism is to correct the TSH value to within the normal range and to contain the symptoms. The hormone deficiency is compensated for by taking thyroid hormones in the form of tablets. This is synthetically produced thyroxine, which those affected usually have to take for life and without interruption. The drug is crept in in increasing doses, on the one hand to determine the individual target dose and, on the other hand, to avoid the symptoms of an overactive thyroid if the dose is increased too quickly.
If the drug is taken correctly, those affected can lead a completely normal life. At the beginning of treatment, the thyroid values ​​are determined monthly by means of a blood sample. If the hypothyroidism is well controlled, the annual blood check is sufficient.
A combination therapy consisting of both thyroid hormones, i.e. T3 and T4, is rarely used when certain synthesis functions are disturbed in the patient, which hinders the conversion of the hormones.
If a drug for the treatment of an overactive thyroid is the cause of the hypofunction, the dose should be changed in consultation with your doctor or the drug discontinued if necessary.

Read more about this at: Treatment of an underactive thyroid

Therapy of congenital hypothyroidism

A lifelong replacement (= substitution) of thyroxine (= T4) with L-thyroxine is necessary to prevent the consequences of the hypothyroidism. It should be started as early as possible because brain damage, once it has occurred, is irreversible.
The dosage of the hormone occurs gradually, i.e. the dose is slowly increased up to a certain hormone concentration, which is ultimately maintained constant.
The goals of the therapy are to ensure that the patient is free of symptoms and to normalize the TSH level in the blood.

Read more on this topic at: Thyronajod®

Regular checks of the hormone level should be carried out in order to check the euthyroid thyroid metabolic status (= normal functional status of the thyroid gland) and to be able to optimally adjust the dosage of the drug.
It is also important to closely observe the growth of the children, which can provide an indication of reduced hormone production.

Read also on this topic Lose weight with hypothyroidism


One that has become very rare these days complication one untreated hypothyroidism is the so-called Myxedema coma. The metabolism of those affected is shut down in a life-threatening manner. Possible symptoms are a Decrease in body temperature, a slow heartbeat, a drop in blood pressure as well as a dangerous one Slowing and flattening of breathing. In some cases you can additionally Myxedema arise. Consequently it comes to doughy swelling different areas of the body, especially in the face and limbs. The myodenal coma in the context of an underactive thyroid should be treated early with the administration of high-dose thyroid hormones. A balance of the electrolyte and water balance as well as the administration of cortisone also play a life-saving role.


As a rule, the symptoms of an underactive thyroid can be overcome by the daily intake the prescribed medication well after a few months.
The intake should be about one half an hour before breakfast with a glass of water so as not to affect the release and absorption of the active ingredient.
In the congenital hypothyroidism depends on the The prognosis is clear from the early start of treatment after diagnosis. The earlier the therapy is started, the more reliably the long-term effects of the physical and mental development delay of an underactive thyroid can be prevented.

Diet and iodine intake- prevention of underactive thyroid

Also the nutrition plays to Prevention of an underactive thyroid a crucial role. It should be on a adequate iodine intake be respected through food, for example in the form of iodized table salt or regular consumption of fish. Because as already mentioned, that is Iodine is an essential component of thyroid hormones. The daily amount of iodine to be consumed is around 200 micrograms.
Excessive consumption of soy products should be avoided as they can impair the function of the thyroid hormones. A balanced one Supply of vitamins and magnesium can have a beneficial effect on the symptoms of hypothyroidism.
In the most common form of hypothyroidism, Hashimoto's thyroiditis, the hypothyroidism cannot be compensated for by an adequate iodine intake.

Hypothyroidism in pregnancy

During pregnancy there is an increased need for iodine in the expectant mother. On the one hand through increased thyroid hormone production, on the other hand the unborn child is dependent on the iodine supply from the mother.
From about the 12th week of pregnancy, the fetus then starts producing thyroid hormones independently. Therefore, an additional iodine intake is recommended for women with known hypothyroidism during pregnancy and breastfeeding.
You can get iodine tablets over the counter from the pharmacy. However, these are not reimbursed by the health insurance company.
A known hypothyroidism, but also a suspected hypothyroidism, should also be treated with thyroid hormones at an early stage. Physical and mental long-term effects on the unborn child can thus be prevented in good time.
As a rule, treatment of the underactive thyroid with the drug L-thyroxine is safe for the child during pregnancy. Consult with your attending gynecologist to adjust the dose of your medication if necessary. Radiation or radioiodine therapy should be avoided during pregnancy. If you are planning to become pregnant and have undergone the aforementioned treatment, you should wait four to six months before conceiving so as not to endanger the development of your child.

Read more about this at: Hypothyroidism in pregnancy