Calcium supplementation to prevent pre-eclampsia - a systematic review
AbstractBackground. Calcium supplementation during pregnancy may prevent high blood pressure and preterm labour. Objective. To assess the effects of calcium supplementation during pregnancy on hypertensive disorders of pregnancy and related maternal and child adverse outcomes. Design. A systematic review of randomised trials that compared supplementation with at least 1 g calcium daily during pregnancy with placebo. Search strategy. The Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) were searched and study s were contacted. Data collection and analysis. Eligibility and trial quality were assessed. Data were extracted and analysed. Main results. There was a modest reduction in the risk of pre-eclampsia with calcium supplementation (relative risk (RR) 0.68, 95% confidence interval (CI): 0.57- 0.81). The effect was greatest for women at high risk of hypertension (RR 0.21, 95% CI: 0.11 - 0.39) and those with low baseline calcium intake (RR 0.32, 95% CI: 0.21 - 0.49). There was no overall effect on the risk of preterm delivery, although there was a reduction in risk among women at high risk of hypertension (RR 0.42, 95% CI: 0.23 - 0.78). There was no evidence of any effect of calcium supplementation on stillbirth or death before discharge from hospital. There were fewer babies with birthweight < 2 500 g (RR 0.83, 95% CI: 0.71 - 0.98). In one study, childhood systolic blood pressure > 95th percentile was reduced (RR 0.59, 95% CI: 0.39 - 0.91). Conclusions. Calcium supplementation appears to be beneficial for women at high risk of gestational hypertension and in communities with low dietary calcium intake. These benefits were confined to several rather small trials, and were not found in the largest trial to date, conducted in a low-risk population. Further research is required.
(South African Medical Journal: 2003 93(3): 224-228)
Copyright remains in the Author’s name. The work is licensed under a Creative Commons Attribution - Noncommercial Works License. Authors are required to complete and sign an Author Agreement form that outlines Author and Publisher rights and terms of publication. The Agreement form should be uploaded along with other submissions files and any submission will be considered incomplete without it [forthcoming].
Material submitted for publication in the SAMJ is accepted provided it has not been published or submitted for publication elsewhere. Please inform the editorial team if the main findings of your paper have been presented at a conference and published in abstract form, to avoid copyright infringement. The SAMJ does not hold itself responsible for statements made by the authors.
Previously published images
If an image/figure has been previously published, permission to reproduce or alter it must be obtained by the authors from the original publisher and the figure legend must give full credit to the original source. This credit should be accompanied by a letter indicating that permission to reproduce the image has been granted to the author/s. This letter should be uploaded as a supplementary file during submission.