Giving vitamin A to women 15 to 45 years old living in poor nations does not cut maternal death rates, scientists said Tuesday in a study that contradicts earlier research showing a dramatic drop in death rates.

Researchers working in Ghana on a trial involving almost 208,000 women found there was no difference in pregnancy-related death rates between those who were given vitamin A pills and those given placebos, or dummy pills.

Vitamin A deficiency is a public health problem in more than half of all countries, particularly in Africa and South-East Asia, hitting young children and pregnant women in low-income countries the hardest.

It is the leading cause of preventable blindness in children and can increase the risk of disease and death from severe infections, according to the World Health Organization.

But Betty Kirkwood, a nutrition and public health specialist at the London School of Hygiene and Tropical Medicine, who led the Ghana study, said her trial showed that giving vitamin A pills did nothing to cut maternal death rates.

“Our results suggest that vitamin A supplementation once a week in women of reproductive age has no beneficial effect on their survival or on the survival of their babies in rural Ghana,” she wrote in the study published in The Lancet medical journal.

The trial results showed there were 39,601 pregnancies and 138 pregnancy-related deaths among those who took vitamin A supplements and 39,234 pregnancies and 148 pregnancy-related deaths in the placebo group - a difference that is not statistically significant.

Kirkwood noted that the Ghana findings contradicted previous results from a trial in Nepal which showed a 44 percent decrease in maternal death among women given vitamin A.

She said the discrepancy showed why it is wise not to rush to change maternal health policies on the basis on one piece of research.

“Research is as important to identify potentially good ideas that do not work, as it is in establishing those that do,” she wrote. “This avoids governments wasting resources on ineffective interventions.”

The Ghana study also found that giving vitamin A to women had no effect on the rate of stillbirths, or neonatal and infant survival - results which echoed those of the Nepal trial.

SOURCE: The Lancet, online May 4, 2010.