POSTPARTUM THYROIDITIS

Abstract

Postpartum thyroiditis is an autoimmune disease of the thyroid gland seen in approximately 8% of women in the postpartum period. Postpartum thyroiditis is a triphasic disease consisting of hyperthyroid, hypothyroid, and euthyroid phases. The pathogenesis of postpartum thyroiditis is not known exactly. However, there are various mechanisms related to pathogenesis. One of these is related to the fetal cell/DNA circulating in the maternal blood to settle in the thyroid gland and the maternal immune system to develop an autoimmune reaction against the thyroid gland in the postpartum period. During pregnancy, fetal cells settle in the thyroid gland and no reaction occurs due to pregnancy-related immunosuppression. Postpartum thyroiditis occurs because immunosuppression disap- pears in the postpartum period. The method of examining fetal cell/DNA in maternal blood during pregnancy is a non-invasive prenatal test. The non-invasive prenatal testing is a screening test used to detect chromosomal anomalies and some other chromosomal defects. However, there is to our knowledge, not enough studies in the literature directly investigating the relationship between the number of fetal cells/DNA in maternal blood and the development of postpartum thyroiditis. Having reviewed the literature around this topic it can be assumed that there can be a difference in the level of damage in the thyroid gland in the postpartum period, depending on the level of difference in the number of fetal cells in the thyroid gland. In addition, future studies will pave the way for studies on the relationship between autoimmune diseases occurring in the post-pregnancy period and the number of fetal DNA/cells in maternal blood during preg- nancy. Therefore, an early diagnosis of pregnancy-related autoimmune diseases will be enabled.

Keywords

• Postpartum thyroiditis
• pregnancy
• hyperthyroidism
• hypothyroidism
• prenatal diagnosis

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