Post-partum thyroiditis in a Mediterranean population: A prospective study of a large cohort of thyroid antibody positive women at the time of delivery

Post-partum thyroiditis (PPT) is a common disease with important clinical sequelae. Its clinical features, association with antimicrosomal antibodies (TPOAb) and long-term prognosis are not thoroughly described in Mediterranean populations. The aims of this study were: 1) to describe clinical features of PPT in a Greek population, 2) to associate TPOAb with PPT presence, and 3) to identify long-term prognosis of PPT. 1,594 consecutive post-partum women were studied within 3 days of their delivery. Women with positive TPOAb were followed-up for one yr for clinical and biochemical evidence of PPT. Incidence of positive TPOAb was 5.2% whereas incidence of PPT was 2.4%. PPT was presented as hyperthyroidism alone (18%), hypothyroidism alone (40%) and hyperthyroidism followed by hypothyroidism (42%). A titer of 1:1600, immediately post-partum, could predict PPT with 97% sensitivity and 91% specificity. History of PPT in previous pregnancies was associated with PPT in the current pregnancy. This association did not exist with maternal age, gestation duration, parity, abortions, sex of the newborn, birth-weight or smoking. Long-term hypothyroidism developed in 21% of women. Observation and post-partum thyroid function testing, where PPT is suspected, seems to constitute the best clinical approach. There is need for long-term follow-up in PPT patients.