Atallah A N, Hofmeyr G J, Duley L
Effective Care Research Unit, University of the Witwatersrand, Frere/Cecilia Makiwane Hospitals, Private Bag 9047, East London 5200, Eastern Cape, South Africa.
Cochrane Database Syst Rev. 2002(1):CD001059. doi: 10.1002/14651858.CD001059.
Calcium supplementation may prevent high blood pressure through a number of mechanisms and may help to prevent preterm labour.
The objective of this review was to assess the effects of calcium supplementation during pregnancy on hypertensive disorders of pregnancy and related maternal and child adverse outcomes.
We searched the Cochrane Pregnancy and Childbirth Group trials register (October 2001) and the Cochrane Controlled Trials Register (Issue 3, 2001) and we contacted study authors.
Randomised trials comparing at least one gram daily of calcium during pregnancy with placebo.
Eligibility and trial quality were assessed. Data extraction was carried out and double entered.
Eleven studies were included, all of good quality. There was a modest reduction in high blood pressure with calcium supplementation (relative risk 0.81, 95% confidence interval 0.74 to 0.89). The effect was greatest for women at high risk of hypertension (relative risk 0.45, 95% confidence interval 0.31 to 0.66) and those with low baseline dietary calcium (relative risk 0.49, 95% confidence interval 0.38 to 0.62). There was also a modest reduction in the risk of pre-eclampsia with calcium supplementation (relative risk 0.68, 95% confidence interval 0.57 to 0.81). The effect was greatest for women at high risk of hypertension (relative risk 0.21, 95% confidence interval 0.11 to 0.39) and those with low baseline calcium intake (relative risk 0.32, 95% confidence interval 0.21 to 0.49). There was no overall effect on the risk of preterm delivery, although there was a reduction in risk amongst women at high risk of hypertension (relative risk 0.42, 95% confidence interval 0.23 to 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 < 2500g (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).
REVIEWER'S CONCLUSIONS: Calcium supplementation appears to be beneficial for women at high risk of gestational hypertension and in communities with low dietary calcium intake. Optimum dosage requires further investigation.
补钙可能通过多种机制预防高血压，并有助于预防早产。
本综述的目的是评估孕期补钙对妊娠高血压疾病及相关母婴不良结局的影响。
我们检索了Cochrane妊娠与分娩组试验注册库（2001年10月）和Cochrane对照试验注册库（2001年第3期），并联系了研究作者。
比较孕期每日至少1克钙与安慰剂的随机试验。
评估纳入标准和试验质量。进行数据提取并双录入。
纳入11项研究，均质量良好。补钙可适度降低高血压风险（相对危险度0.81，95%可信区间0.74至0.89）。对高血压高危女性（相对危险度0.45，95%可信区间0.31至0.66）和基线饮食钙含量低的女性（相对危险度0.49，95%可信区间0.38至0.62）影响最大。补钙也可适度降低子痫前期风险（相对危险度0.68，95%可信区间0.57至0.81）。对高血压高危女性（相对危险度0.21，95%可信区间0.11至0.39）和基线钙摄入量低的女性（相对危险度0.32，95%可信区间0.21至0.49）影响最大。对早产风险无总体影响，不过高血压高危女性的早产风险有所降低（相对危险度0.42，95%可信区间0.23至0.78）。没有证据表明补钙对死产或出院前死亡有任何影响。出生体重<2500g的婴儿较少（RR 0.83，95%CI 0.71 - 0.98）。在一项研究中，儿童期收缩压>第95百分位数有所降低（RR 0.59，95%CI 0.39 - 0.91）。
补钙似乎对妊娠高血压高危女性和饮食钙摄入量低的社区有益。最佳剂量需要进一步研究。
