The human endocrine system produces biologically active substances called hormones. One of them is thyroid-stimulating hormone, the norm in women of which indicates good performance of the endocrine glands. During pregnancy, TSH allows you to monitor the condition of the expectant mother and fetus. At the same time, an increase in the content of the hormone signals the onset of a threat to the health of the baby. In other cases, a change in thyroid-stimulating hormone levels may indicate a number of thyroid diseases, cancerous growth, and other diseases.
What is called thyrotropin or TSH
Thyroid stimulating hormone has other names – thyrotropin, or thyrotropin, abbreviated as TSH. According to the international classification, its abbreviation is tsh.
This hormone is produced by the anterior part of the pituitary gland, which is an appendage of the brain and at the same time – a small endocrine gland. The chemical composition of thyrotropin includes complex proteins. The main task of TSH is to regulate the amount of thyroid hormones produced – T4 (thyroxine) and T3 (triiodothyronine).
These substances produced by the thyroid gland are responsible for a number of processes that occur in the human body:
- regulate metabolism;
- stimulate the efficiency of the heart and blood vessels;
- participate in the activity of the reproductive system;
- regulate the psycho-emotional state.
These processes are dependent on thyroid-stimulating hormone. It is he who controls the production of both T4 and T3 in their normal amount. However, there is also an inverse relationship. With an increase in the amount of T4, indicating an increased activity of the gland, the production of TSH decreases. Knowing what thyroid-stimulating hormone is in women helps in understanding the relationship between thyrotropin, thyroxine and triiodothyronine. Indeed, if necessary, a joint check is performed on the content of these three active substances in the blood – TSH, as well as T3 and T4.
The norm of thyroid-stimulating hormone in women in the lower limit is equal to 0.4 μIU / ml (in the abbreviation IU is used – international units), and in the upper limit – 4.0 μIU / ml. Such rather widely varying indicators are caused by the fact that the TSH value can vary depending on a number of factors:
- changes of seasons;
- daily period;
- the presence of pregnancy;
- strong emotional stress;
- performing physical work.
As soon as a woman becomes pregnant, it immediately affects the level of thyrotropin, which changes depending on the stages of the child’s development. At the initial stage of pregnancy, in the first trimester, part of the TSH functions are performed by chorionic gonadotropin (hCG). This biologically active substance is produced in large quantities by the shell of the embryo. Thanks to hCG, the body begins to tune in to support the development of the fetus. The rate of thyrotropin during such a period varies within small limits – from 0.1 to 0.4 μIU / ml.
As the baby grows in the womb, the TSH also changes. So, in the second trimester, thyroid-stimulating hormone is in the range from 0.3 to 2.8, and in the third – from 0.4 to 3.5 μIU / ml. With an increase in thyrotropin levels, an urgent examination of a pregnant woman is necessary.
After the onset of 18 years, TSH indicators should not go beyond the upper or lower limits and the norm for women after 50 years remains the same.
It should be remembered that after the fortieth birthday, experts recommend that the fair half must be tested for thyroid hormones, since the upcoming menopause can negatively affect the thyroid gland.
Increased thyrotropin levels
An increase in the level of TSH indicates the presence of pathologies in the body. They can be:
- disruption of the thyroid gland, and sometimes the adrenal glands;
- manifestation of neoplasms;
- hypothyroidism (lack of thyroid hormones);
- mental disorders;
- excessive use of preparations containing iodine;
- preeclampsia (complication of pregnancy) in severe forms.
In addition to these diseases, the level of thyrotropin can also increase in a number of severe pathologies, for example, during hemodialysis.
Decrease in thyrotropin levels
A decrease in TSH indices develops in the following cases:
- severe stress;
- long-term diet or fasting;
- hyperthyroidism (high levels of thyroid hormones);
- the presence of various forms of goiter (increase in the size of the thyroid gland);
- taking hormonal drugs.
The decision on the need to take an analysis for hormones is made by the doctor. Often, this direction is issued for problems with the thyroid gland. It is important to take into account that women have this disease more often than men.