The effect of vitamin D and calcium supplementation on inflammatory biomarkers, estradiol levels and severity of symptoms in women with postpartum depression: a randomized double-blind clinical trial

Objectives: Postpartum depression (PPD) is a major depressive disorder. Vitamin D deficiency may play a role in PPD pathogenesis. This study was designed to determine the effect of vitamin D and calcium supplementation on the severity of symptoms and some related inflammatory biomarkers in women with PPD.Materials and Methods: Eighty-one women with a PPD score >12 participated in this study. A total of 27 patients were randomly assigned into three groups (1:1:1 ratio) to receive either 50,000 IU vitamin D3 fortnightly + 500 mg calcium carbonate daily; or 50,000 IU vitamin D3 fortnightly + placebo of calcium carbonate daily, or placebo of vitamin D3 fortnightly + placebo of calcium carbonate daily (placebo group) for 8 weeks. At the baseline and end of the study, the severity score of PPD, levels of 25-hydroxy vitamin D, calcium, tumor necrosis factor-alpha (TNFα), interleukin 6 (IL6) and estradiol were measured.Results: The PPD score had more reduction in the vitamin D + calcium and vitamin D + calcium placebo groups than that of the placebo group (−1.7 ± 3.44, −4.16 ± 5.90 and 0.25 ± 2.81, respectively; p = 0.008). The effect of vitamin D on the PPD score was larger when vitamin D was given alone than given together with calcium (p = 0.042 and p = 0.004, respectively). No significant differences in estradiol, IL6 and TNFα were observed between the three groups.Discussion: Vitamin D may be effective in improving the clinical symptoms of PPD; however, the mechanism of the effect might not entirely operate through inflammatory and/or hormonal changes.