VOA英语2010年-Pregnant Women Who Take Iron（在线收听）

New research reinforces the importance of prenatal iron supplementation for good birth outcomes and continued good health for growing children.

Research over the past 20 years have pointed to the importance of micronutrients - substances found in small amounts in foods that make a big difference. One of the most important micronutrients for pregnant women is iron. Iron is vital to the development of a fetus' central nervous system, says Parul Christian, a nutritionist working at the Johns Hopkins School of Public Health.

"Early iron deficiency can change the neuro-anatomy of the brain, and impact the neuro-chemistry of the central nervous system and brain metabolism, that are important for cognitive development, for sensory-motor development."

But providing vitamin and micronutrient supplements to all pregnant women can be a significant financial burden in low income countries. Some experts argue that it's enough to give infants iron supplements after they're born. That was part of the reason Christian and her colleagues decided to study poor women in Nepal a decade ago. Some of the women got supplements without iron and folic acid, another important micronutrient, while others got supplements with both micronutrients.

"That study was completed in 2001 and showed iron and folic acid supplementation could have an impact on infant and later childhood survival," Christian says.

That earlier study strengthened the case for supplements, but Christian's new research shows an even longer term impact on children who received iron in utero. She and her colleagues returned to Nepal, and were able to test the neurological development on children who were now on the brink of adolescence.

"The offspring of the mothers who had received iron and folic acid during pregnancy through three months postpartum had improved intellectual functioning including improved working memory and inhibitory control, which are domains capturing executive function, and they had better fine motor functioning ability as well."

Christian adds there was a qualitative difference between these older children and those whose mothers had received the supplements without iron.

She says these outcomes should remove any doubts lingering in the minds of health planners about whether or not to spend extra dollars to make sure that each pregnant woman receives iron supplementation during pregnancy. And she says in places such as the Asian subcontinent - where iron deficiency is endemic - supplementing with iron delivers an even larger bang for the public health buck.

Christian's research appears in the Journal of the American Medical Association.