Hypothyroidism Levels - Importance of Thyroid Hormones During Pregnancy

established thought that there is no physiologically important transport of thyroid hormones during development and that such hormones would not be necessary for regular growth of the fetal nervous system is likely to have contributed to the common lack of understanding and approval of results of many epidemiological and clinical studies. credible reason can not be nominated for the association between early maternal hypothyroxinemia and reduced neurodevelopmental result of a child. It is complicated to solve the very serious and often permanent neurological injury of cretins (with normal thyroid function when iodine offer is complete), the successful avoidance of serious injury to the nervous system in early postnatal management of congenital hypothyroidism babies, including those of children without a thyroid.

a lack of defensive action maternal triiodothyronine (T3) compared to thyroxine (T4), showed the deep regions with iodine deficiency, according to a number of unanswered problems. The original conclusion is often acquired during the previous 15 years in experimental animals and in man, at this point clearly indicate the function to move the maternal thyroid hormone in the nervous system maturation during fetal life and propose reasonable details of these issues. Regardless of the results of this novel, and even with the rising recognition of the significant functions of maternal T4 in serious obstacle to nervous system damage in cases of congenital hypothyroidism, it still proves that if thyroid hormone is needed during the first trimester is less certain, otherwise it should be delivered by the mother, because nothing is released products until mid-trimester.

Since this problem is crucial for understanding the likely importance of the first quarter of free thyroxine (FT4) in fetal maturation of the nervous system, attention is drawn to the data currently available for experimental animals and to humans. Both T4 and T3 are available until the beginning of the fetus, with extremely low amounts can be found when it is circulating in the mother are significantly low. As soon as that happens, prenatal and postnatal developmental changes can be detected. Nuclear receptors for thyroid hormones (TRS) are also located in the early stages of the fetal nervous system, to some extent occupied by T3, in some animal models, with levels rising throughout the moments of very strong birth of neurons of the cerebral cortex.

Several genes in the nervous system reacts to a lack of thyroid hormone are known, often in the postnatal period, the time of the nervous system extension that matches the last period of pregnancy and early postnatal period in humans.