Evidence map›Paper›PMID 24621141›Full record

SynthesisBJOG : an international journal of obstetrics and gynaecology2014

Low-dose calcium supplementation for preventing pre-eclampsia: a systematic review and commentary.

G J Hofmeyr, J M Belizán, P von Dadelszen, Calcium and Pre-eclampsia (CAP) Study Group

Open access · hybridAbstract readSystematic Review
PubMed Full text at PMC Publisher
In one paragraph

Synthesis in BJOG : an international journal of obstetrics and gynaecology, 2014. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 40 papers, 4 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
40citing papers in PubMed, 4 pooled it
14.6field-weighted citation impact, top 1% of its field
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

40 citing papers in PubMed, 4 syntheses or guidelines pooled it, 106 citations in OpenAlex.

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  11. Toward personalized management of chronic hypertension in pregnancy.American journal of obstetrics and gynecology · 2022
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4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

4 authors at 3 institutions in 3 countries.

G J HofmeyrEffective Care Research Unit, East London Hospital Complex/University of the Witwatersrand/University of Fort Hare, East London, Eastern Cape, South Africa.
J M Belizán
P von Dadelszen
Calcium and Pre-eclampsia (CAP) Study Group
Child and Family Research Institute · CAInstituto de Efectividad Clínica y Sanitaria · ARUniversity of the Witwatersrand · ZA

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

backgroundEpidemiological data link low dietary calcium with pre-eclampsia. Current recommendations are for 1.5-2 g/day calcium supplementation for low-intake pregnant women, based on randomised controlled trials of ≥1 g/day calcium supplementation from 20 weeks of gestation. This is problematic logistically in low-resource settings; excessive calcium may be harmful; and 20 weeks may be too late to alter outcomes.

objectivesTo review the impact of lower dose calcium supplementation on pre-eclampsia risk. SEARCH STRATEGY AND SELECTION CRITERIA: We searched PubMed and the Cochrane Pregnancy and Childbirth Group trials register. DATA COLLECTION AND ANALYSIS: Two authors extracted data from eligible randomised and quasi-randomised trials of low-dose calcium (LDC, <1 g/day), with or without other supplements. MAIN

resultsPre-eclampsia was reduced consistently with LDC with or without co-supplements (nine trials, 2234 women, relative risk [RR] 0.38; 95% confidence interval [95% CI] 0.28-0.52), as well as for subgroups: LDC alone (four trials, 980 women, RR 0.36; 95% CI 0.23-0.57]); LDC plus linoleic acid (two trials, 134 women, RR 0.23; 95% CI 0.09-0.60); LDC plus vitamin D (two trials, 1060 women, RR 0.49; 0.31-0.78) and a trend for LDC plus antioxidants (one trial, 60 women, RR 0.24; 95% CI 0.06-1.01). Overall results were consistent with the single quality trial of LDC alone (171 women, RR 0.30; 95% CI 0.06-1.38). LDC plus antioxidants commencing at 8-12 weeks tended to reduce miscarriage (one trial, 60 women, RR 0.06; 95% CI 0.00-1.04).

conclusionsThese limited data are consistent with LDC reducing the risk of pre-eclampsia; confirming this in sufficiently powered randomised controlled trials would have implications for current guidelines and their global implementation.

Indexed as

Dietary SupplementsCalcium, DietaryFemaleHumansHypertensionPre-EclampsiaPregnancyPregnancy Complications, CardiovascularRandomized Controlled Trials as TopicTreatment OutcomeCalcium, DietaryCalcium replacementcalcium supplementeclampsialow-dose calciumpre-eclampsia

Identifiers

PMID24621141
PMCPMC4282055
OpenAlexW2041943288

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.