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SYDNEY - Fortifying bread with folic acid to avoid birth defects could increase the number of twins born to New Zealand and Australian women, child health experts have warned.
A new review by a team at Melbourne's Murdoch Children's Research Institute has concluded there is "possible evidence" that women who take extra folic acid to reduce the risk of spinal defects are more likely to have twins.
This would have public health implications, with two babies more likely to be premature and underweight, and put extra pressure on families, the research team noted.
The team said the issue must be investigated further before Australia and New Zealand push ahead with mandatory fortification.
Transtasman regulator Food Standards Australia New Zealand has proposed adding folic acid to bread-making flour to reduce spina bifida and other neural tube defects in babies.
But the move stalled last year after opposition from manufacturers and some scientists.
The Murdoch team was funded by the standards body to review six studies on folic acid and twins.
"Overall there is possible evidence, rather than probable or convincing evidence, for a relationship between periconceptional folic acid intake and increased twinning," the team wrote in the Medical Journal of Australia.
The Australia and New Zealand Food Regulation Ministerial Council will meet in May to decide the issue.
- AAP