PTH and depressive symptom measurement: RCT- randomised controlled trial, GA- gestational age, MDD - major depressive disorder, VDD- vitamin D deficiency, IU- International units, Vit D- Vitamin D, BDI- Beck depression inventory, EPDS- Edinburgh Postnatal Depression Scale, CRP- C-reactive protein, Ca- Calcium, P- phosphate, PTH- Parathyroid hormone, HDRS- Hamilton Depression Rating Scale, NA- not available