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Medicina & Laboratorio

2022, Number 1

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Medicina & Laboratorio 2022; 26 (1)

Thyroid physiology and hypothyroidism in pregnancy. A review

Rueda-Galvis MV, Builes-Barrera CA

Language: Spanish
References: 83
Page: 15-33
PDF size: 198.41 Kb.


ABSTRACT

During pregnancy, multiple physiological changes are generated at the hormonal level to successfully carry out pregnancy. One of the hormonal axes with the most important changes that have a direct impact on fetal development and maternal well-being is the thyroid axis, which presents multiple modifications to reach the needs of thyroid hormone for both the mother and the fetus, primarily in the early stages of pregnancy. Changes in the amount of hormone transport proteins, increased stimulation and production of thyroid hormones, increased re- nal clearance of iodine, and alteration in deiodinase activity are included within these modifications. These mechanisms offer enough thyroid hormone to the fetus, which is dependent on the maternal supply. An imbalance in any of these can lead to the development of hypothyroidism with multiple complications, such as pregnancy loss and gestational hypertension, among others. Timely screening and early treatment can avoid these adverse outcomes, hence the importance of knowing and understanding the regulation of the thyroid axis in pregnancy.


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