London, Jun 23 (IANS): Taking iron supplements daily during pregnancy can reduce the chances of having a small baby as well as anaemia, says a new study.

Studies of two million women found that taking even a tiny amount of iron cut the risk of anaemia by 12 percent and low birth weight by three percent, BBC reported.

Serious iron deficiency tends to affect several women in poorer countries.

The World Health Organisation (WHO) currently recommends an iron dose of 60 mg per day for pregnant women.

The British Medical Journal study analysed the results of more than 90 randomised trials and studies involving pregnant women in countries including China and Tanzania.

For every additional 10 mg of iron taken each day, up to a maximum of 66 mg per day, the risks of anaemia and low birth weight decreased, the study said.

Birth weight was found to increase by 15 grams with each 10 mg of iron taken per day.

But researchers found no reduction in the risk of premature birth as a result of iron use, BBC said.

Previous studies have suggested there could be a higher risk of low birth weight and premature birth in pregnant women with anaemia.

The study said iron deficiency is the most common cause of anaemia during pregnancy, especially in low and middle income countries, affecting about 32 million pregnant women in 2011.

"The recently estimated prevalence of iron deficiency anaemia during pregnancy in Europe was estimated to be 16.2 percent in 2011," said Batool Haider, study author from the department of epidemiology and nutrition at Harvard University's school of public health.

However, experts said women who are intolerant to iron can suffer from indigestion, bloating and other stomach problems. But reducing the dose should also reduce the side effects.