Khoiri, M.A., Lumbanraja, S.N., Aldiansyah, D., Siregar, M.F.G., Sitepu, M. and Tala, M.R. 2022. Calcium serum concentration among pregnant women in a tertiary hospital and its satellite hospital in Medan, Indonesia. Majalah Obstetri & Ginekologi. 30, 2 (Aug. 2022), 78–83. DOI:https://doi.org/10.20473/mog.V30I22022.78-83.