Giving magnesium sulphate to woman at risk of pre-term birth can significantly reduce the risk of cerebral palsy in infants, according to a new study.
Cerebral palsy is a disabling condition that affects around one in every 500 newborn babies overall, and up to one-in-ten very premature babies.
"There is now enough evidence to support giving magnesium sulphate to women at risk of very preterm birth as a protective agent against cerebral palsy for their baby," said lead researcher, Lex Doyle, who works at the Department of Obstetrics and Gynaecology at the Royal Women's Hospital and the University of Melbourne in Australia.
It is usually given as a slow infusion through a vein, but can also be given as an injection into the muscle.
Although it's not clear how magnesium protects the brain, but it is essential for many processes that keep cells working normally.
It may protect against harmful molecules that can damage or kill cells, and it improves blood flow under some circumstances.
For the study, Cochrane researchers reviewed data from five trials of antenatal magnesium sulphate therapy, which together included 6,145 babies.
Overall, 63 women at risk of very pre-term birth had to be given magnesium sulphate to prevent one case of cerebral palsy in the baby.
The side effects of the treatment included flushing, sweating, nausea, vomiting, headaches and palpitations.
However, according to the researchers, there was no increase in major complications in mothers due to magnesium therapy.