A confusing situation in the clinic practice: Isolated maternal hypothyroxinemia

Year 2024, , 91 - 98, 31.08.2024

Zekeriya Keskin

https://doi.org/10.56941/odutip.1507480

Abstract

Isolated maternal hypothyroxinemia (IMH) is a common problem in the clinic practice. There is a normal maternal thyroid stimulating
hormone (TSH) level with a low maternal free thyroxine (FT4) level. The aim of this review is to explain IMH in the light of current
literature and to contribute to clinicians in the management of IMH. Iodine deficiency is the most important factor in etiology. The
effects of IMH on the pregnant women and the fetus are not clear. However, it is a serious concern among clinicians, especially
considering the importance of the effect of thyroid hormones on fetal brain development. As for the treatment of IMH, the number
of studies conducted is not sufficient and there is no consensus and evidence on levothyroxine treatment. However, there is a
consensus on iodine supplementation and it is recommended to take 250 mg of iodine daily. As a result, IMH is a problem that should
be taken seriously during pregnancy and care should be taken regarding its diagnosis and treatment. Additionally, more research is
needed on the effects and treatment of IMH on pregnant women and fetal health.

Keywords

Isolated maternal hypothyroxinemia, Thyroid hormone, Pregnant, Fetus, Iodine deficiency

Klinik pratikte kafa karıştıran bir durum: İzole maternal hipotiroksinemi

Abstract

İzole maternal hipotiroksinemi (İMH) klinik pratikte sık görülen bir sorundur. Düşük anne serbest tiroksin (FT4) düzeyi ile birlikte
normal bir anne tiroid stimulan hormon (TSH) düzeyi mevcuttur. Bu derlemenin amacı İMH’nin güncel literatür eşliğinde gözden
geçirilmesi ve İMH’nın yönetiminde klinisyenlere katkıda bulunmaktır. Etyolojide en önemli etken olarak iyot eksikliği
bulunmaktadır. İMH’nın gebe ve fetüs üzerindeki etkileri net değildir. Ancak tiroid hormonlarının özellikle fetal beyin gelişimi
üzerindeki etkisinin önemi düşünüldüğünde klinisyenler arasında ciddi bir endişe kaynağıdır. İMH tedavisinde ise yapılan çalışma
sayısı yeterli olmayıp levotiroksin tedavisi konusunda fikir birliği ve kanıt yoktur. Ancak iyot takviyesi konusunda görüş birliği
vardır ve günlük 250 mg iyot alınması önerilir. Sonuçta İMH gebelikte ciddiye alınması gereken, tanı ve tedavisi konusunda dikkatli
olunması gereken bir problemdir. Ayrıca İMH’nın gebe ve fetüs sağlığı üzerine etkileri ve tedavisi konusunda daha fazla araştırmaya
ihtiyaç vardır.

Keywords

İzole maternal hipotiroksinemi, Tiroid hormonu, Gebe, Fetüs, İyot eksikliği

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