Evaluation of risk-factor-based screening for thyroid peroxidase antibody positivity in pregnancy

SummaryObjective To determine whether risk-factor-based screening for thyroid dysfunction in pregnancy performs well for detecting thyroid peroxidase antibodies (TPOAb), a marker for autoimmune thyroid disease. Study Design We prospectively evaluated pregnant women for thyroid dysfunction using The Endocrine Society's eleven screening questions. Serum was analysed for TPOAb. Result We enrolled 546 women. TPOAb positivity was higher in women with a personal (odds ratio (OR) = 8·0; 95% confidence interval (CI) = 1·7–37·4; P = 0·02) or family history of thyroid disease (OR = 2·7; 95% CI = 1·3–5·7; P = 0·02). There was no association between the number of positive responses and TPOAb positivity (P = 0·41). Risk-factor-based screening missed 18 women (33%) with TPOAb. Conclusion One-third of women with TPOAb were missed by the case-finding method. A personal or family history of thyroid disease was most strongly associated with TPOAb positivity.