Lyndal Powell I got sunshine … Lyndal Powell, with son Bailey, Julie Cunningham and Laura Grant in Rouse Hill. A study found low vitamin D in pregnancy can affect a child's language skills. Photo: Danielle Smith
MOTHERS with low vitamin D levels during pregnancy are twice as likely to have children who experience language difficulties requiring clinical treatment, Australian scientists have found in research that reignites the debate on whether all pregnant mothers should be tested for deficiency.
Researchers from the Telethon Institute for Child Health Research in Perth looked at vitamin D concentrations of more than 700 pregnant caucasian women, with regular follow-ups until the child was 17. The most significant language impairment was seen in those aged between five and 10 years.
Language development impairment that continued into primary school years affected 6 per cent of Australian children the lead author of the study, Professor Andrew Whitehouse, said.
''What causes it has been a mystery for many years,'' he said
"The developing baby is completely reliant on the mother for its vitamin D levels and what we have shown is that this might have an impact on the child's brain development."
Direct sunlight is the main source of vitamin D. Deficiency had increased over the past two decades and now affects about 60 per cent of caucasian women. This was largely due to sunscreen and improved skin cancer awareness, Professor Whitehouse, whose study was published in journal Pediatrics, said.
''We certainly don't endorse women going out into the sun unprotected, so the next step is to look at whether Vitamin D supplements in pregnancy could reduce the risk of language problems for children.''
Rebecca Mason, who is the deputy director of the University of Sydney's Bosch Institute, said the results added more weight to a growing call for universal testing for vitamin D deficiency during pregnancy to be carried out.
The government had argued the cost of testing for deficiency combined with wide variation in individual test results meant only women considered at risk of deficiency should be tested.
''But there is an accumulating amount of data showing an association between low vitamin D levels and some adverse outcomes,'' Professor Mason said.
Lyndal Powell is five months pregnant with her second child but said she had not been tested for a vitamin D deficiency during either of her pregnancies. If testing was made standard, she said she would support it.
''If it can be done while they are carrying out other tests, then why not,'' Mrs Powell, from Kellyville Ridge, said.
''To be honest when I exercise outside at 9.30am I don't wear sunscreen because the sun isn't so harsh, so I would assume my levels are fine. But it would be good to know for sure.''