Document Type: Systematic Review
Faculty of Nursing and Midwifery, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Introduction: Hypothyroidism is a common endocrine disorder that, occurs in 2% to 5% of pregnancies. During pregnancy, the body’s demand for thyroid hormones increases, which affects the growth of the fetus. In case of inadequate and defective production of thyroid hormones, adverse effects on the development of the fetus will appear. Lack of symptoms of hypothyroidism during pregnancy causes late diagnosis, resulting in a lack of timely treatment and impaired fetal development. The purpose of this review is to investigate the effects of mothers’ hypothyroidism on children.
Methods: This systematic review study was performed by searching the Google Scholar, PubMed, and Science Direct databases for the period between 2018 and 2008 by including the keywords for hypothyroidism, thyroid hormones, growth in the uterus. A number of papers related to the use of the Cochran seven-step model were obtained and analyzed for the final analysis.
Results: Thyroid hormones play a vital role in fetal development for ectopic life, through direct and indirect mechanisms that, act on the development of the fetus. Thyroid hormones help in the synthesis of surfactant and lung evolution, stimulation of secretion of catecholamine, increased beta-adrenergic receptors of the lung and stimulation: the activity of sodium and potassium pumps in the alveolar cell surface, the effect on the transmission of brain neurotransmitters and growth hormone, and nervous function.
Conclusions: Thyroid hormones play a key role in fetal development. Therefore, in women with hypothyroidism, especially when not treated, it affects the development of the fetus and increases the incidence of complications in neonates. So early diagnosis of hypothyroidism and adequate and timely treatment during pregnancy is cornerstone in preventing impaired growth and development of the fetus and the occurrence of defects in childhood.