Hypothyroidism in pregnancy current guidelines, prevalence, and implications for maternal and fetal health
DOI:
https://doi.org/10.18203/2320-6012.ijrms20251764Keywords:
Hypothyroidism, Pregnancy, Maternal and fetal healthAbstract
Hypothyroidism during pregnancy is a common endocrine disorder that can drastically impact the mother and fetus in the process of development. The two types of hypothyroidism in pregnancy are distinguished as overt and subclinical, with the latter being more prevalent. Subclinical hypothyroidism (SCH) is commonly caused by autoimmune thyroid disorders and iodine deficiency. In iodine-sufficient areas, hypothyroidism is caused by Hashimoto’s thyroiditis, whereas, in iodine-deficient areas, hypothyroidism is primarily caused by iodine deficiency. Diagnosing hypothyroidism during pregnancy is often challenging because its symptoms often mimic those of normal pregnancy. During pregnancy, thyroid function undergoes significant alterations. The disruption of the normal functioning of the hypothalamic-pituitary-thyroid axis causes fluctuations in both thyroid stimulating hormone (TSH) and thyroxine (T4) levels. Elevated human chorionic gonadotropin (hCG) and estrogen levels trigger the thyroid gland to increase hormone production. If hypothyroidism is not managed properly throughout pregnancy, it could lead to preeclampsia and premature delivery and neurodevelopmental concerns in the baby. It is recommended to consider hypothyroidism screening for women with autoimmune conditions or an existing history of thyroid disease due to their increased risk. The main treatment for pregnant women with hypothyroidism is levothyroxine, whose dosage is regulated to meet the increased demand for thyroid hormones. Continuous monitoring of free T4 levels and TSH is crucial in maintaining hormonal balance. The present review explores the prevalence of hypothyroidism during pregnancy, physiological changes, maternal and fetal complications, and the evidence-based guidelines for the management. Following current recommendations and proper treatment minimizes the risks for the mother and the baby.
Metrics
References
Sullivan SA. Hypothyroidism in pregnancy. Clin Obstet Gynecol. 2019;62(2):308-19. DOI: https://doi.org/10.1097/GRF.0000000000000432
Taylor PN, Lazarus JH. Hypothyroidism in pregnancy. Endocrinol Metabol Clin. 2019;48(3):547-56. DOI: https://doi.org/10.1016/j.ecl.2019.05.010
Okosieme OE, Lazarus JH. Hypothyroidism in Pregnancy. 2019.
Mandal RC, Bhar D, Das A, Basunia SR, Kundu SB, Mahapatra C. Subclinical hypothyroidism in pregnancy: An emerging problem in Southern West Bengal: A cross-sectional study. J Nat Sci, Biol, Med. 2016;7(1):80. DOI: https://doi.org/10.4103/0976-9668.175080
Gietka-Czernel M, Glinicki P. Subclinical hypothyroidism in pregnancy: controversies on diagnosis and treatment. Pol Arch Intern Med. 2021;131(3):266-75. DOI: https://doi.org/10.20452/pamw.15626
Gosi SKY, Garla VV. Subclin Hypothyroid. 2019.
Khattak RM, Saifullah Z, Khadija G, Fayyaz A, Zaman S, Gul M, et al. Regional influences on nutritional iodine status of pregnant women in Pakistan. Thyroid. 2018;28(11):1538-46. DOI: https://doi.org/10.1089/thy.2017.0267
Puthiyachirakal MA, Hopkins M, AlNatsheh T, Das A. Overview of thyroid disorders in pregnancy. Maternal Health, Neonatol Perinatol. 2025;11(1):9. DOI: https://doi.org/10.1186/s40748-025-00208-9
Zhang B, Xi S, Zhan Z, Zhang Y, Lu F, Yuan X. Maternal obesity and the incidence of large-for-gestational-age newborns in isolated hypothyroxinemia pregnancies: a comparative cohort study. Reproduct Biol Endocrinol. 2025;23(1):60. DOI: https://doi.org/10.1186/s12958-025-01394-z
Paschou SA, Bletsa E, Papazisi M, Mili N, Kanouta F, Kassi GN, et al. Screening and management of major endocrinopathies during pregnancy: an update. Endocrine. 2023;80(1):10-9. DOI: https://doi.org/10.1007/s12020-022-03237-y
Chen X, Jin B, Xia J, Tao X, Huang X, Sun L, et al. Effects of thyroid peroxidase antibody on maternal and neonatal outcomes in pregnant women in an iodine‐sufficient area in China. Int J Endocrinol. 2016;2016(1):6461380. DOI: https://doi.org/10.1155/2016/6461380
Grossklaus R, Liesenkötter K-P, Doubek K, Völzke H, Gaertner R. Iodine deficiency, maternal hypothyroxinemia and endocrine disrupters affecting fetal brain development: a scoping review. Nutrients. 2023;15(10):2249. DOI: https://doi.org/10.3390/nu15102249
Yap YW, Onyekwelu E, Alam U. Thyroid disease in pregnancy. Clinical medicine. 2024;23(2):125. DOI: https://doi.org/10.7861/clinmed.2023-0018
Cignini P, Cafà EV, Giorlandino C, Capriglione S, Spata A, Dugo N. Thyroid physiology and common diseases in pregnancy: review of literature. Journal of prenatal medicine. 2012;6(4):64.
Singh S, Sandhu S. Thyroid disease and pregnancy. 2019.
Springer D, Jiskra J, Limanova Z, Zima T, Potlukova E. Thyroid in pregnancy: From physiology to screening. Critical reviews in clinical laboratory sciences. 2017;54(2):102-16. DOI: https://doi.org/10.1080/10408363.2016.1269309
Pangkahila ES, Tangkas LPWS. Thyroid Dysfunction in Pregnancy: A Literature Review. European J Med Health Sci. 2023;5(3):12-6. DOI: https://doi.org/10.24018/ejmed.2023.5.3.1669
Lucaccioni L, Ficara M, Cenciarelli V, Berardi A, Predieri B, Iughetti L. Long term outcomes of infants born by mothers with thyroid dysfunction during pregnancy. Acta Bio Medica: Atenei Parmensis. 2020;92(1):21010.
Lundgaard MH, Sinding MM, Sørensen AN, Handberg A, Andersen S, Andersen SL. Maternal hypothyroidism and the risk of preeclampsia: a Danish national and regional study. Maternal Health, Neonatol Perinatol. 2024;10(1):16. DOI: https://doi.org/10.1186/s40748-024-00186-4
Nazarpour S, Tehrani FR, Simbar M, Azizi F. Thyroid dysfunction and pregnancy outcomes. Iranian J Reproduc Med. 2015;13(7):387.
Alexander EK, Pearce EN, Brent GA, Brown RS, Chen H, Dosiou C, et al. Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and the postpartum. Thyroid. 2017;27(3):315-89.
Solha STG, Mattar R, dos Santos Teixeira PdF, Chiamolera MI, Maganha CA, Zaconeta ACM, et al. Screening, diagnosis and management of hypothyroidism in pregnancy. Revista Brasileira de Ginecologia e Obstetrícia/RBGO Gynecol Obst. 2022;44(10):999-1010. DOI: https://doi.org/10.1055/s-0042-1758490
Toloza FJ, Derakhshan A, Männistö T, Bliddal S, Popova PV, Carty DM, et al. Association between maternal thyroid function and risk of gestational hypertension and pre-eclampsia: a systematic review and individual-participant data meta-analysis. The Lancet Diab Endocrinol. 2022;10(4):243-52.
Batistuzzo A, Ribeiro MO. Clinical and subclinical maternal hypothyroidism and their effects on neurodevelopment, behavior and cognition. Arch Endocrinol Metabol. 2020;64(1):89-95. DOI: https://doi.org/10.20945/2359-3997000000201
Korevaar TI, Muetzel R, Medici M, Chaker L, Jaddoe VW, de Rijke YB, et al. Association of maternal thyroid function during early pregnancy with offspring IQ and brain morphology in childhood: a population-based prospective cohort study. Lancet Diab Endocrinol. 2016;4(1):35-43. DOI: https://doi.org/10.1016/S2213-8587(15)00327-7
Anagnostis P, Lefkou E, Goulis DG. Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and the postpartum. Thyroid. 2017;27(9):1209-10. DOI: https://doi.org/10.1089/thy.2017.0155
Dhillon-Smith R, Coomarasamy A. TPO antibody positivity and adverse pregnancy outcomes. Best Pract Res Clin Endocrinol Metabol. 2020;34(4):101433. DOI: https://doi.org/10.1016/j.beem.2020.101433
Lee SY, Pearce EN. Testing, monitoring, and treatment of thyroid dysfunction in pregnancy. The J Clin Endocrinol Metabol. 2021;106(3):883-92. DOI: https://doi.org/10.1210/clinem/dgaa945
Poppe K, Bisschop P, Fugazzola L, Minziori G, Unuane D, Weghofer A. European thyroid association guideline on thyroid disorders prior to and during assisted reproduction. European Thyroid J. 2021;9(6):281-95. DOI: https://doi.org/10.1159/000512790
Chan SY, Marsh MS, Gilbert J, Boelaert K, Evans C, Dhillon-Smith R, et al. Management of Thyroid Disorders in Pregnancy. BJOG. 2025;4:68. DOI: https://doi.org/10.1111/1471-0528.18088
De Groot L, Abalovich M, Alexander EK, Amino N, Barbour L, Cobin RH, et al. Management of thyroid dysfunction during pregnancy and postpartum: an Endocrine Society clinical practice guideline. J Clin Endocrinol Metabol. 2012;97(8):2543-65. DOI: https://doi.org/10.1210/jc.2011-2803
Luo J, Yuan J. Effects of levothyroxine therapy on pregnancy and neonatal outcomes in subclinical hypothyroidism. Int J Gen Med. 2022;15:6811. DOI: https://doi.org/10.2147/IJGM.S366981
Nazarpour S, Ramezani Tehrani F, Sajedi F, Rahmati M, Bidhendi Yarandi R, Azizi F. Lack of beneficiary effect of levothyroxine therapy of pregnant women with subclinical hypothyroidism in terms of neurodevelopment of their offspring. Arch Gynecol Obst. 2024;309(3):975-85. DOI: https://doi.org/10.1007/s00404-023-06954-5
Liu H, Shan Z, Li C, Mao J, Xie X, Wang W, et al. Maternal subclinical hypothyroidism, thyroid autoimmunity, and the risk of miscarriage: a prospective cohort study. Thyroid. 2014;24(11):1642-9. DOI: https://doi.org/10.1089/thy.2014.0029
Lemieux P, Yamamoto JM, Nerenberg KA, Metcalfe A, Chin A, Khurana R, et al. Thyroid laboratory testing and management in women on thyroid replacement before pregnancy and associated pregnancy outcomes. Thyroid. 2021;31(5):841-9. DOI: https://doi.org/10.1089/thy.2020.0609
Dhanwal DK. High prevalence of subclinical hypothyroidism during first trimester of pregnancy in North India. Indian J Endocrinol Metab. 2021;3:83.
Iqbal A. Iodine deficiency and thyroid dysfunction in pregnant women of Khyber Pakhtunkhwa. Pak J Med Sci. 2012;2:8723.
Dayan CM, Panicker V. Hypothyroidism and depression. Eur Thyroid J. 2009;2:98.
Alexander EK, Pearce EN, Brent GA, Brown RS, Chen H, Dosiou C, et al. Guidelines of the American Thyroid Association for the diagnosis and management of thyroid disease during pregnancy and the postpartum. Thyroid. 2017;27(3):315-89. DOI: https://doi.org/10.1089/thy.2016.0457
Glinoer D. The regulation of thyroid function during normal pregnancy: importance of the iodine nutrition status. Best Prac Res Clin Endocrinol Metabol. 2004;18(2):133-52. DOI: https://doi.org/10.1016/S1521-690X(04)00011-9
Moleti M, Trimarchi F, Vermiglio F. Thyroid physiology in pregnancy. Endocr Pract. 2014;20(6):589-96. DOI: https://doi.org/10.4158/EP13341.RA
Lucaccioni L, Ficara M, Cenciarelli V, Berardi A, Predieri B, Iughetti L. Long term outcomes of infants born by mothers with thyroid dysfunction during pregnancy. Acta Bio Medica: Atenei Parmensis. 2020;92(1):202110.
Andersen SL, Knøsgaard L, Olsen J, Vestergaard P, Andersen S. Maternal thyroid function, use of antithyroid drugs in early pregnancy, and birth defects. J Clin Endocrinol Metabol. 2019;104(12):6040-8. DOI: https://doi.org/10.1210/jc.2019-01343
Vissenberg R, Manders VD, Mastenbroek S, Fliers E, Afink GB, Ris-Stalpers C, et al. Pathophysiological aspects of thyroid hormone disorders/thyroid peroxidase autoantibodies and reproduction. Human Reprod. 2015;21(3):378-87. DOI: https://doi.org/10.1093/humupd/dmv004
Toloza FJ, Derakhshan A, Männistö T, Bliddal S. Association between maternal thyroid function and risk of gestational hypertension and pre-eclampsia: a systematic review and individual-participant data meta-analysis. Lancet Diab Endocrinol. 2022;10(4):243-52. DOI: https://doi.org/10.1016/S2213-8587(22)00007-9
Je H. Maternal thyroid deficiency during pregnancy and subsequent neuropsychological development of the child. N Engl J med. 1999;341:549-55. DOI: https://doi.org/10.1056/NEJM199908193410801
Lazarus JH, Bestwick JP, Channon S, Paradice R, Maina A, Rees R, et al. Antenatal thyroid screening and childhood cognitive function. New England J Med. 2012;366(6):493-501. DOI: https://doi.org/10.1056/NEJMoa1106104
Poppe K, Velkeniers B, Glinoer D. The role of thyroid autoimmunity in fertility and pregnancy. Nature Clin Pract Endocrinol Metabol. 2008;4(7):394-405. DOI: https://doi.org/10.1038/ncpendmet0846
Nazarpour S, Ramezani Tehrani F, Amiri M, Bidhendi Yarandi R, Azizi F. Levothyroxine treatment and pregnancy outcomes in women with subclinical hypothyroidism: a systematic review and meta-analysis. Arch Gynecol Obst. 2019;300:805-19. DOI: https://doi.org/10.1007/s00404-019-05245-2
Casey BM. Subclinical hypothyroidism and pregnancy. Obst Gynecolog Surv. 2006;61(6):415-20. DOI: https://doi.org/10.1097/01.ogx.0000223331.51424.9b
Manning R, Iyer J, Bulmer JN, Maheshwari A, Choudhary M. Are we managing women with Recurrent Miscarriage appropriately. A snapshot survey of clinical practice within the United Kingdom. J Obst Gynaecol. 2021;41(5):807-14. DOI: https://doi.org/10.1080/01443615.2020.1803241
Downloads
Published
How to Cite
Issue
Section
