The Magpie Trial: a randomised trial comparing magnesium sulphate with placebo for pre-eclampsia
Ly-Mee Yu and Doug Altman with Lelia Duley (Oxford) and international multicentre collaborators
Pre-eclampsia in childbirth is an important cause of morbidity and mortality for the mother and her child. Eclampsia, the occurrence of seizures superimposed on pre-eclampsia, is rare but associated with a far worse outcome than pre-eclampsia. Anticonvulsants are used for women with pre-eclampsia in the belief that they reduce the risk of eclampsia, and so improve outcome. Internationally there is controversy about whether an anticonvulsant should be given to women with pre-eclampsia. If one is used, however, magnesium sulphate seems to be the best choice even though there is little reliable evidence about the overall benefits and hazards.
The Magpie Trial was a large international randomised trial comparing magnesium sulphate with placebo for treatment of women with pre-eclampsia. The primary outcomes were eclampsia and death of the baby. Data collection ended late in 2002 with just over 10,000 women recruited. The main results were published a few months later and showed that magnesium sulphate halves the risk of eclampsia, and probably reduces the risk of maternal death. There did not appear to be substantive harmful effects to mother or baby in the short term.
Longer term follow-up of a subsample of the babies was completed in 2004, and the effects on other measures of serious maternal and neonatal morbidity have been assessed. A paper describing the findings has been submitted for publication.
Publications: 26, 99