Role of High Dose Calcium in the Prevention of Preeclampsia

Abstract

Objectives: To assess the effect of supplementation of high dose of calcium(2gm) in prevention of preeclampsia.Materials & Methods: A randomized controlled clinical trial on 272 healthy nulliparous woman were randomly allocated into two groups by means of a computer generation randomization list. From 20 weeks of gestation until delivery who received 2gm of oral elemental calcium per day (n=127 )were assigned to high dose calcium group or the study group and 145 women were assigned to low dose calcium or control group , receiving 500 mg of calcium per day. Ten women (3.67%) were lost to follow up after randomization (4 in the study group and 6 in the control group) . Thus a total of 123 woman in the study group and 139 in the control group were included in the final analysis. Data was collected by standard questionnaire, clinical examination and investigations and statistical analysis was performed by student’s t-test, chi square tests. P<0.05 was statistically significant.Results: Preeclampsia developed in Study Group were 5.7% and Control Group 13.7% and the difference was statistically significant (Chi-squares - 4.65, df =1, p = 0.031). There were 2.43% (3 of 123 women) preterm delivery in the study group and 7.91% (11 of 39 women) in the control group. So, there was a significantly lower risk of preterm delivery in the study group ( p = 0.049). Intrauterine growth retardation (IUGR) was found in 3.25% and 9.35% of women in the study and the control groups respectively. The incidence is higher in the control group when compared to the study group (p = 0.045).Conclusion: Calcium intake is beneficial for both pregnant women and her unborn child. Daily supplementation with 2 grams of calcium during pregnancy significantly reduced the risk of preeclampsia, preterm labor and IUGR. So, high dose calcium should be supplemented to all women during pregnancy in developing countries where preeclampsia and preeclampsia related morbidities and mortality are quite high.Bangladesh J Obstet Gynaecol, 2013; Vol. 28(2) : 66-70

Calcium for pre‐eclampsia prevention: A systematic review and network meta‐analysis to guide personalised antenatal care

“…Of the 720 records identified, 30 RCTs (20 445 women) were eligible for the calcium supplementation versus placebo/no therapy meta‐analysis 16–45 ; and one additional RCT (272 women) was eligible for the high‐ versus low‐dose calcium NMA (Figure S1). 46 Reasons for exclusion are detailed in Table S2, and included seven continuing trials 47–53…”

“…The NMA (25 trials, 15 038 women) included 24 trials in the meta‐analysis (details presented in Table 1), plus a trial of 2000 mg/day versus 500 mg/day elemental calcium from 20 weeks of gestation, in healthy nulliparous women (at low risk), with low baseline calcium intake in India 46 . Trials of high‐dose and low‐dose calcium, with roughly similar frequency, enrolled women at high risk (trials 18,22,27,31,32,34,38,39,43 with high dose; trials 16–18,23–26,36 with low dose) or women at low risk (trials 19,21,28–30,35,42,44–46 with high dose; trials 20,33,37,41and46 with low dose) of pre‐eclampsia, women with a low average baseline dietary intake of calcium (trials 18,19,22,28,30–32,34,35,39,40,44–46 with high dose; trials 16–18,20,23–26,33,36,37,41,46 with low dose) and women who initiated calcium supplementation early (trials 28,29,44 with high dose; trials 16,25,37 with low dose) or late (trials 18,19,21,22,27,30–32,34,35,38–40,42–46 with high dose; trials 17,18,20,23,24,26,33,36,41,46 with low dose) in pregnancy. The six trials among populations with adequate average calcium intake (trials 21,27,29,38,42,43 ) were not included in the NMA because they were all were high‐dose calcium trials and their inclusion would have violated the assumption of transitivity.…”

“…Of the 720 records identified, 30 RCTs (20 445 women) were eligible for the calcium supplementation versus placebo/no therapy meta-analysis ; and one additional RCT (272 women) was eligible for the high-versus low-dose calcium NMA (Figure S1). 46 Reasons for exclusion are detailed in Table S2, and included seven continuing trials. [47][48][49][50][51][52][53] Trials of calcium versus placebo/no therapy were primarily from individual countries, usually in the Americas (Table 1); four trials were conducted in multiple countries, involving sites in Argentina, Bangladesh, Colombia, Egypt, India, Peru, South Africa, the USA, Vietnam and Zimbabwe.…”

Different Doses of Calcium Supplementation to Prevent Gestational Hypertension and Pre-Eclampsia: A Systematic Review and Network Meta-Analysis

“…Among the included 48 studies, only 17 studies ( 14 , 16 , 17 , 48 – 51 , 53 , 54 , 56 – 58 , 60 , 62 , 64 – 66 ) reported the specific random grouping. In addition, only 12 studies ( 14 , 48 – 50 , 53 , 54 , 56 – 58 , 62 , 65 , 66 ) described the detailed methodology for hiding the random distribution sequences, leading to high risk of selection bias.…”

“…Therefore, implementation and measurement bias was at high risk. Furthermore, a risk of loss of follow-up bias was seen as there was a loss of follow-up in nine studies ( 14 , 15 , 17 , 49 , 52 , 56 , 60 , 62 , 64 ). Only nine studies ( 14 – 16 , 48 , 50 , 62 , 64 – 66 ) reported research protocols, leading to a high-risk of reporting bias ( Figure 2 ).…”