Table 1.

The steps of study analysis.

Proceedings		Stage
Obtaining written inform consent form and completing the questionnaire		Recruitment and completion of the questionnaire
Determining groups according to their status of vitamin DCollection of the laboratory samples Obtaining fasting blood samples. Assessment of serum concentration of vitamin D in Masjed-Solayman immediately and storing Shustar samples at −80°C		Classification
Obtaining fasting blood samples 3 months after termination of the intervention for those without maintenance vitamin D therapy (groups A1, A3, B1, and B3) and for all women at delivery time. Obtaining cord blood sample from all participantsStart of intervention Prescription of vitamin D according to various protocols (A1-3 and B1-3) for intervention groups		Replication of laboratory samples
Follow-up of pregnancy outcomes and neonatal calcium and vitamin D status		Follow-up