Clinical importance of thyroid peroxidase Autoantibodies (TPO - Ab) Determination in pregnancy

Abstract

Pregnant women with positive thyroid peroxidase autoantibodies (TPO - Ab) run an increased risk for developing postpartum thyroiditis (PPT). Eight clinically healthy pregnant women in third timester were screened for TPO - Ab titres by radioimmunoassay (RIA) technique and were followed 3 - 4 months postpartum. During pregnancy TPO - Ab seropositivity was seen in 17.5% cases. Serum thyroxine (T) and thyroid stimulating hormone (TSH) levels done only in seropositive cases were with in normal limmits. After follow up 21.25% cases showed TPO - Ab seropositivity 3 - 4 months postpartum. The rise in  TPO - Ab titre was very signficant in 23.5% of seropositive case (5% of the total) who developed mildthyrotoxic phase of PPT. Serum T level were increased above normal limits while serum TSH levels were decreased in them along with the clinical findings. Twenty nonpregnant women were included in the study as controls who were all seronegative for TPO-Ab showeing significantly high prevalence of TPO - Ab during pregnancy (P< 0.001).