Transient post-partum thyroid dysfunction and postnatal depression.

In the course of a population study of thyroid dysfunction in pregnancy and the post-partum period, 65 women, considered to be antibody-positive (microsomal and thyroglobulin), and 82 antibody-negative women were assessed for postnatal depression at 6-8 weeks post partum. The women were also assessed for the development of post-partum thyroid dysfunction. Of the 147 women, 22 met DSM-III criteria for major depression. The presence of autoantibodies showed little association with depressed mood but there was a minor association of postnatal depression with actual thyroid dysfunction in that incidence of the latter condition was higher in depressed women (Raskin scale P less than 0.01; Edinburgh scale P less than 0.05; Montgomery-Asberg scale P less than 0.1). Three of eight mothers with thyroid dysfunction had major depression and were depressed on all three scales.