Society for Maternal-Fetal Medicine

View all recommendations from this society

May 1, 2019

Don’t screen asymptomatic pregnant women for subclinical hypothyroidism.

Subclinical hypothyroidism (SCH) is defined as an elevated serum TSH level in the presence of a normal free T4 level and is found in 2% to 5% of otherwise healthy pregnant women. SCH is unlikely to progress to overt hypothyroidism during pregnancy. While some authorities and organizations have recommended routine screening for all pregnant women and subsequent treatment with levothyroxine, two recent, large (>100,000 women) prospective randomized clinical trials of screening and treatment for SCH demonstrated no effect of treatment on offspring IQ at age 5 years. Because treatment for SCH has not resulted in a beneficial effect on outcomes, routine screening for SCH is not currently recommended. Targeted screening for women at risk for overt hypothyroidism is still appropriate.


These items are provided solely for informational purposes and are not intended as a substitute for consultation with a medical professional. Patients with any specific questions about the items on this list or their individual situation should consult their physician.

How The List Was Created

As a national medical specialty society, the Society for Maternal-Fetal Medicine relies on the input of any number of its committees in the development of various documents. In the case of the items included in this list, the Publications Committee reviewed the literature and evidence from SMFM’s published documents for possible topics. For SMFM’s first set of five recommendations a sub-group of the Committee initially developed a list of 10 items that the Committee then ranked for the top five with input and suggestions by the Society’s Executive Committee. For SMFM’s second set of recommendations, the sub-group of the Committee developed a list of 12 items that the Committee then ranked for the top five, again soliciting input and suggestions by the Society’s Executive Committee. For SMFM’s third set of five recommendations, the sub-group of the Publications Committee developed a list of 10 items that the Committee ranked for the top five, again soliciting input and suggestions by the Society’s Executive Committee. The final lists have been reviewed and approved by the Society’s Document Review Committee and Executive Committee.

SMFM’s disclosure and conflict of interest policy can be found at www.smfm.org

Sources

Thyroid disease in pregnancy. Practice Bulletin No. 148. American College of Obstetricians and Gynecologists. Obstet Gynecol 2015; 125:996–1005.

Lazarus JH, Bestwick JP, Channon S, Paradice R, Maina A, Rees R, et al. Antenatal thyroid screening and childhood cognitive function [published erratum appears in N Engl J Med 2012;366:1650]. N Engl J Med 2012;366:493–501.

Society for Maternal-Fetal Medicine. Screening for thyroid disease during pregnancy. Contemporary OB/GYN; August 2012. https://www.smfm.org/publications/88-screening-for-thyroid-disease-in-pregnancy