To help prevent preeclampsia and preterm birth-;common complications in pregnancy that can be fatal to women and newborns-;low-dose calcium supplementation (equivalent to one 500-milligram pill per day) may be as effective as the World Health Organization (WHO)’s recommended high-dose calcium supplementation (equivalent to three 500-milligram pills taken throughout each day), according to a new study led by Harvard T.H. Chan School of Public Health and collaborators in India and Tanzania.