Thyroid function 48h after delivery as a marker for subsequent postpartum depression

Physiological changes during gestation and after delivery are associated with postpartum thyroid dysfunction, which is due to thyroid autoimmunity in some cases. Postpartum thyroid dysfunction, in turn, has been associated with postpartum depression (PPD). The aim of the present study was to evaluate whether thyroid function immediately after delivery can predict postpartum depression at 8 weeks and 32 weeks after delivery. This study examined 1053 postpartum Spanish women without a previous history of depression. We evaluated depressive symptoms at 48h, 8 weeks and 32 weeks postpartum and used a diagnostic interview to confirm major depression for all probable cases. Free thyroxin (fT4), thyroid-stimulating hormone (TSH), thyroid peroxidase antibodies (TPOAb) and C-reactive protein (CRP) were assayed at 48h postpartum. Binary and multivariate logistic regression analyses were performed to determine independent risk factors for PPD. Although 152 women (14.4%) had high TPOAb (>27IU/mL) and slightly elevated TSH concentrations with normal fT4, we did not find any association between thyroid function and PPD. This thyroid dysfunction was not associated with CRP concentrations that were outside of the normal range (>3mg/L). We conclude that thyroid function at 48h after delivery does not predict PPD susceptibility.