A multi-vitamin administered daily to pregnant women can help curb infant mortality in developing countries as it reduces the risk of premature births and increases infant birth weight, shows a trial carried out in rural Bangladesh.

Premature birth is a leading cause of infant mortality in many parts of the world.

The findings suggest that the supplement contains 15 essential micronutrients is superior to the supplements available in many developing countries.

"Our study shows that women in undernourished societies should be given a multiple micronutrient supplement during pregnancy," said study leader Keith West Jr, professor at Johns Hopkins Bloomberg School of Public Health.

"It increases birth size because the babies stay in the womb longer and when that happens they are born a little larger and better equipped to handle life outside the womb," West added.

For this study, the researchers recruited roughly 45,000 pregnant women in rural Bangladesh beginning in December 2007, and assigned them to receive either a daily multi-vitamin or an iron-folic acid supplement.

The babies born in the multi-vitamin group were 12 percent less likely to be born at a low birth weight (under 2.5 kg) and 11 percent less likely to be stillborn.

On average, the infants born to mothers in the multi-vitamin group were born two to three days later than those in the iron-folic acid group, giving them more time to bulk up before birth, and were born an average of 55 grams larger.

The findings were published in JAMA: The Journal of the American Medical Association.