The Debate over Thyroid-Function Screening in Pregnancy

Maternal hypothyroidism in pregnancy has been associated with a range of adverse outcomes, most importantly miscarriage, preterm delivery, and reduced cognitive function in offspring. 1 In surveys, almost half the obstetricians in private practices in Maine 2 and the majority of obstetricians in a Boston academic center 3 reported ordering thyroid-function tests for screening in pregnancy. Most guidelines recommend the testing of thyroid function only in women at increased risk, known as case finding, rather than universal screening. 4 , 5 The case-finding approach overlooks a large number of women with abnormal thyroid-function tests 1 , 6 ; however, in a randomized trial, universal thyroid-function screening and . . .