Objective: The etiology of postpartum psychosis (PP) remains unclear. In this study, we examined thyroid-stimulating hormone, free T4, free T3, cortisol, prolactin, follicle-stimulating hormone, luteinizing hormone (LH), and dehydroepiandrosterone sulfate (DHEAS) levels in PP.
Method: The study included 23 patients who were hospitalized with the diagnosis of PP within the first 4 weeks after delivery and 30 age-matched healthy controls. Organic etiological factors were excluded. Blood samples were obtained from all participants at the same time of the day. In PP patients, blood samples were obtained within the first 24 h after hospitalization.
Results: Mean ages of PP and control groups were 26.2 ± 5.5 and 27.6 ± 5.1 years, respectively. The frequency of vaginal delivery was significantly higher in the PP compared with the control group (p = 0.011). The fT3 levels were significantly lower in the PP compared with the control group, while the fT3 levels were within normal physiological limits (p = 0.034) and no significant differences were found with regard to other hormones. To examine the effect of breastfeeding on the results, the control group was further divided into two subgroups: breastfeeding (BFC) and non-breastfeeding (NBFC). The fT4 levels (within normal physiological limits) and prolactin levels were significantly higher in the PP compared with NBFC (p = 0.013 vs p = 0.007). LH levels were 3.11 ± 3.47 mIU/mL in the PP group, 1.48 ± 2.45 mIU/mL in BFC and 4.56 ± 3.69 mIU/mL in NBFC, but for the LH levels, the only significant difference was between the control groups (p = 0.027).
Conclusion: The results of thyroid function tests in our study suggest a condition that develops impaired thyroid functions secondary to acute psychotic episode rather than an underlying thyroid disease. Comprehensive prospective studies, including follow-up data, may better explain the relationships between thyroid function and PP. In our study, there was no evidence for the possible role of DHEAS, prolactin, and LH hormones. However, changes in the hormone profile according to breastfeeding status suggest that the effects of breastfeeding on hormones may also be important.