Infants whose mothers take vitamin D supplements during pregnancy and infancy are less likely to get respiratory infections, according to research from the University of Auckland.
The study conducted from April 2010 to July 2011, with 260 pregnant women, found that vitamin D supplementation during pregnancy and infancy resulted in a smaller proportion of infants making primary care visits for respiratory infections.
The study's findings were only recently released.
The University of Auckland paediatrics professor, Dr Cameron Grant said based on work done in this study, the team behind it would be making recommendations for more universal vitamin D supplementation during pregnancy.
The study began with vitamin D supplementation during pregnancy so that it could be ensured when the babies were born they had normal vitamin D status.
Dr Grant said a baby at birth was completely dependant upon their mother for their vitamin D, so if the mother was vitamin D deficient during pregnancy, the baby would be vitamin D deficient at birth.
"So by starting the vitamin D during pregnancy we were able to ensure that when the babies were born they had a normal vitamin D status. We then continued vitamin D supplementation after the baby was born."
The mother took the vitamin D from 27 weeks gestation until the baby was born, and then the baby took vitamin D from birth to six months of age.
Then the vitamin D group was compared with a control group taking placebo.
Dr Grant said what was found in this study was primary care visits for respiratory infections decreased and that continued up to age 18 months after the vitamin D implementation was stopped.
He said the finding suggested that the vitamin D that was given during pregnancy in early infancy had caused some change in the baby's immune system so that they were either less likely to get a respiratory infection, or if they got a respiratory infection they were less likely to become as unwell as a baby whose vitamin D status was poor.
He said this study had shown the importance of implementation of the supplement daily.
The study was completed in a population living in South Auckland for whom vitamin D deficiency was common, and in whom respiratory infections in early childhood were a big problem.
He said the study highlighted the importance of doing studies in populations who have the most risk of poor health, and the most potential to gain from an intervention such as this.