Pregnancy: warning on multivitamins
13 March 2009
Pregnant women should be cautioned against exceeding dose recommendations when using multivitamins because of potential fetal risks.
Professor Julie Owens, head of the school of paediatrics and reproductive health at the University of Adelaide, said doctors should not underestimate the dosage that some women might consume.
‘Concern is now growing that people think that if something is a good thing, more of it must be even better,’ she told Medical Observer.
‘A significant number of women may be exposing themselves and their baby to excessive... or potentially dangerous amounts of vitamins, by taking 2-10 times the recommended daily levels.’
Professor Owens told the conference that a US study found that a proportion of pregnant women took such large amounts of multivitamins that they exceeded the daily upper intake limits for some individual nutrients.
Very high dose vitamin A, D and E, for example, have been linked to congenital defects (conditions present at birth) in offspring.
While the evidence was clear that periconceptual folic acid (a vitamin taken around the time of conception) reduced the risk of neural tube defects (such as spina bifida), new research findings suggested more studies were needed to clarify safe levels at different gestational ages (stages of pregnancy), Professor Owens said.
‘We have experimental evidence in animals that there might be adverse outcomes in terms of allergic airways disease later on in the baby’s life,’ she said.
‘There is also some evidence linking the amount of folate a woman consumes in pregnancy to a risk of wheezing later on in her infant.’
The recommended daily dose of folate in Australia for pregnant women (0.6 mg per day) was moderate and it was important to ‘stick to current guidelines’, she said.
Last Reviewed: 13 March 2009
