Thyroid stimulating hormone (TSH) ≥2.5mU/l in early pregnancy: prevalence and subsequent outcomes

Carty, D. M., Doogan, F., Welsh, P. , Dominiczak, A. F. and Delles, C. (2017) Thyroid stimulating hormone (TSH) ≥2.5mU/l in early pregnancy: prevalence and subsequent outcomes. European Journal of Obstetrics and Gynecology and Reproductive Biology, 210, pp. 366-369. (doi: 10.1016/j.ejogrb.2017.01.048) (PMID:28153744)

Abstract

Objective: There remains controversy over how women with abnormal thyroid function tests in pregnancy should be classified. In this study we assessed the proportion of women with thyroid stimulating hormone (TSH) ≥ 2.5 mU/l in a large obstetric cohort, and examined how many have gone on to develop thyroid disease in the years since their pregnancy. Study design: 4643 women were recruited and samples taken in early pregnancy between 2007 and 2010. Thyroid function tests were analysed in 2014; in women with raised TSH computerised health records and prescription databases were used to identify thyroid disease detected since pregnancy. Results: 58 women (1.5%) had a TSH over 5 mU/l and 396 women (10.3%) had TSH between 2.5 and 5 mU/l. Women with TSH > 5mU/l delivered infants of lower birthweight than those with TSH < 2.5 mU/l; there were no other differences in obstetric outcomes between the groups. Of those who have had thyroid tests since their pregnancy, 78% of those with TSH > 5 mU/l and 19% of those with TSH between 2.5 and 5 mU/l have gone on to be diagnosed with thyroid disease. Conclusions: Using a TSH cut-off of 2.5 mU/l in keeping with European and US guidelines means that over 12% of women in this cohort would be classified as having subclinical hypothyroidism. Treatment and monitoring of these women would have major implications for planning of obstetric services.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Doogan, Dr Flora and Welsh, Professor Paul and Dominiczak, Professor Anna and Delles, Professor Christian and Carty, Dr David
• Authors: Carty, D. M., Doogan, F., Welsh, P., Dominiczak, A. F., and Delles, C.
• College/School: College of Medical Veterinary and Life Sciences > School of Cardiovascular & Metabolic Health; College of Medical Veterinary and Life Sciences > School of Medicine, Dentistry & Nursing
• Journal Name: European Journal of Obstetrics and Gynecology and Reproductive Biology
• Publisher: Elsevier
• ISSN: 0301-2115
• ISSN (Online): 1872-7654
• Published Online: 25 January 2017
• Copyright Holders: Copyright © 2017 Elsevier Ireland Ltd.
• First Published: First published in European Journal of Obstetrics and Gynecology and Reproductive Biology 210:366-369
• Publisher Policy: Reproduced in accordance with the copyright policy of the publisher