Value of combined clinical information and thyroid peroxidase antibodies in pregnancy for the prediction of postpartum thyroid dysfunction

PROBLEM: To investigate the utility of thyroid peroxidase antibodies (TPOAb) in early pregnancy combined with clinical information for prediction of postpartum thyroid dysfunction (PPTD) within 1 year postpartum. METHOD OF STUDY: We studied 98 pregnant women by determining their TPOAb levels in early pregnancy, as well as their serum thyrotropin and free thyroid (fT4) levels at 6 and 12 months postpartum. Furthermore, they answered a questionnaire and physical examination was performed by only one examiner. RESULTS: Of the 98 women, 10 were positive TPOAb in early pregnancy. The overall risk of PPTD within 1 year of follow-up was 10.2% (95% CI 4.1-16.3). Risk of PPTD was significantly higher among women with a family history of thyroid disease, TPOAb positive and presenting goiter in early pregnancy. The sensitivity, specificity and positive predictive value of TPOAb in PPTD prediction were 60.0%, 95.5% and 60%. Restricting screening to women with a family history of thyroid disease or presenting goiter increases the positive predictive value from 60% to 82.4%. CONCLUSION: Our results suggest that TPOAb could be used as a screening test for PPTD prediction at least among women who present a high risk of developing PPTD.