Maternal thyroid failure

The association between this neurobehavioral disorder and thyroid abnormalities, and a possible role of thyroid hormone in ADHD pathogenesis is discussed here. An overview of published data on this issue and, more specifically, the possibility that even subtle maternal thyroid failure during gestation, caused by iodine deficiency, can be responsible for the disorder, are the subjects of the present chapter. 

In two conditions, namely when the functional capacity of the thyroid gland is unpaired (i.e. autoimmune thyroid disease) or during pregnancy in healthy women residing in iodine-deficient areas, the maternal thyroid gland cannot easily adapt to the increased hormonal requirements, and variable degrees of maternal thyroid failure (MTF) may occur over the course of gestation. 

When neurological results were related to early-pregnancy maternal thyroid function, it was seen that all 11 ADHD+ children were born to the ID area mothers whose thyroid function proved more heavily compromised than that of the 5 ADHD— mothers, and that 7/8 (87.5%) of the ID area mothers who experienced thyroid failure generated ADHD+ children. It is worth noting, however, that individual TSH levels fell consistently within the normal range in all but two of these women,... 

Maternal hypothyroxinemia, caused by iodine intake which fails to meet the increased needs imposed by the conceptus, is hkely to be much more frequent than primary thyroid failure and thyroid autoimmune disease. 

When the fetal thyroid is impaired (as in congenital hypothyroidism) maternal T4 has a protective effect on the fetal brain and on other fetal tissues . This might mitigate adverse effects of fetal thyroid failure on the developing brain. It appeared important to determine whether, or not, T3... 

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