The Magpie Trial: a randomised trial comparing magnesium sulphate with placebo for pre-eclampsia. Outcome for children at 18 months
OBJECTIVE
To assess the long-term effects of in utero exposure to magnesium sulphate for children whose mothers had pre-eclampsia.


DESIGN
Assessment at 18 months of age for children whose mothers were recruited to the Magpie Trial (recruitment 1998-2001 ISRCTN 86938761), which compared magnesium sulphate with placebo.


SETTING
Follow-up of children born at 125 centres in 19 countries across five continents.


POPULATION
A total of 6922 children were born to women randomised before delivery at follow-up centres. Of these, 2271 were not included for logistic reasons and 168 were excluded (101 at a centre where <20% were contacted, 40 whose death or disability was due to a problem at conception or embryogenesis and 27 whose parent/s opted out). Therefore, 4483 children were included in follow-up, of whom 3283 (73%) were contacted.


METHODS
Assessment by questionnaire, with interview and neurodevelopmental testing of selected children.


MAIN OUTCOME MEASURES
Death or neurosensory disability at age of 18 months.


RESULTS
Of those allocated magnesium sulphate, 245/1635 (15.0%) were dead or had neurosensory disability at 18 months compared with 233/1648 (14.1%) allocated placebo (relative risk [RR] 1.06, 95% CI 0.90-1.25), and of survivors, 19/1409 (1.3%) had neurosensory disability at 18 months compared with 27/1442 (1.9%) (RR 0.72, 95% CI 0.40-1.29). There were no substantial differences in causes of death or in the risk of individual impairments or disabilities.


CONCLUSIONS
The lower risk of eclampsia following prophylaxis with magnesium sulphate was not associated with a clear difference in the risk of death or disability for children at 18 months.