Experts say the discovery a 'gamechanger' and will now investigate if taking iron supplements could help prevent defects.
A study's found women who experience low iron levels during pregnancy are much more likely to have a baby with heart disease.
Researchers looked at data from 16-thousand mothers and linked anaemia in early pregnancy to increased chances of congenital heart disease.
Experts say the discovery a 'gamechanger' and will now investigate if taking iron supplements could help prevent defects.

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