ENDO: High Normal Thyroid Levels Linked to Miscarriage
WEDNESDAY, June 23 (HealthDay News) -- Women in their first trimester of pregnancy who have thyroid function test results in the upper half of the normal range but have negative thyroid antibody test results are at a higher risk for miscarriage, according to research presented at the annual meeting of The Endocrine Society, held from June 19 to 22 in San Diego.
As part of a larger study that included 4,562 women who were screened for thyroid stimulating hormone (TSH) and thyroid peroxidase in the first trimester of pregnancy, Alex Stagnaro-Green, M.D., of the George Washington University School of Medicine in Washington, D.C, and colleagues randomized women to a universal-screening group or a case-finding group and stratified these women as high or low risk for thyroid disease.
The researchers found 4,123 women in the first trimester of pregnancy who were thyroid antibody negative with a TSH of 5.0 or lower. The findings revealed a significant increase in the rate of miscarriage in thyroid antibody negative pregnant women with TSH levels between 2.5 and 5.0, compared to antibody negative women with TSH levels below 2.5 (6.1 versus 3.6 percent).
"There has been an ongoing discussion as to whether or not the normal range for thyroid function tests is too broad," Stagnaro-Green said in a statement. "This study provides clear evidence that the normal range for thyroid function tests during pregnancy needs to be redefined."
