Maternal thyroid parameters in pregnant women with different ethnic backgrounds: Do ethnicity-specific reference ranges improve the diagnosis of subclinical hypothyroidism?

Pregnant women with a sub-Saharan African background had a lower prevalence of TAI and TSH levels as compared with women from other backgrounds. The use of ethnicity-specific TSH cut-offs in early pregnancy was not more specific for the diagnosis of SCH as compared to the use of the institutional cut-off.