Pregnant women in Ireland have severe vitamin D deficiencies threatening the growth of their babies, a health study has warned.
Researchers who tracked 64 expectant mothers found their intake of the vitamin - essential for children's healthy teeth and bone development - was 80% below recommended levels.
The study found that less than a quarter of pregnant women surveyed consumed oily fish such as salmon or mackerel, the best dietary source of vitamin D.
One reason may be because women are often guided towards plain carbohydrate foods, which are low in the vitamin, during early pregnancy to ease nausea, said experts.
Fionnuala McAuliffe, professor of obstetrics and gynaecology at University College Dublin and the National Maternity Hospital, led the study. She said: "Our findings reveal that pregnant women in Ireland have a poor dietary intake of vitamin D.
"Their diet, which includes meat, eggs and fortified breakfast cereals, simply does not provide the recommended levels of the vitamin."
The research findings published in the European Journal of Clinical Nutrition warned that vitamin D insufficiencies during pregnancy can cause reduced bone growth in babies before birth and lead to poor bone development in early childhood.
Severe deficiencies can cause childhood rickets, a softening and weakening of the bones.
The scientists involved in the study called for pregnant women to be encouraged to take vitamin D supplements.
The vitamin is known as the "sunshine vitamin" as it can be obtained from sun exposure and people living in northern European may suffer deficiencies. The study involved 64 women, over 18, from early pregnancy to childbirth and excluded anyone taking vitamin D supplements.