A new study touts the benefits of multivitamins for women during pregnancy, suggesting that they're associated with a significantly reduced risk of babies with a low birth weight.

The study, known as a meta-analysis, pulled together data from 13 previous studies comparing babies whose mothers took multivitamin supplements to those of women who took only prenatal iron-folic supplementation or a placebo.

The findings from Dr. Prakesh Shah and colleagues at Mount Sinai Hospital in Toronto were published Tuesday in the Canadian Medical Association Journal.

Shah says low birth weight and related complications are considered the most common cause of death in children under age five worldwide, and there's a possibility of reducing underweight birth rates by 17 per cent.

"The birth weight of infants was 54 grams [two ounces] higher on average among those whose mothers were given micronutrients than among those whose mothers received iron-folic acid supplementation," said the research paper.

The authors estimate that 75 million births occur in developing countries where — at best — mothers receive iron-folic acid supplements.

"If all of these women were given multimicronutrient supplementation, our most conservative calculations indicate that about 1.5 million births of low-birth-weight infants could be averted worldwide every year," they wrote.

In a commentary, two doctors at the Aga Khan University in Karachi, Pakistan, noted there are some limitations to the study.

Address poverty

But Dr. Zulfiqar Bhutta and Dr. Batool Azra Haider said strategies to prevent and manage maternal under-nutrition and micronutrient deficiencies in developing countries are a priority.

"However, these strategies may require multiple interventions," they wrote.

These include "fortified food supplements or conditional cash transfers to address household food insecurity, micronutrient interventions that address iron-deficiency anemia and other deficiencies."

As well, measures are needed to reduce the burden of maternal infections such as HIV and malaria, they said.