Iron deficiency is one of the most common nutritional problems in the world and affects many pregnant women. Now new research shows that anemia isn't just a problem for expectant mothers: It can seriously impact their babies.
University of Rochester neonatologist Sanjiv Amin explains that late in pregnancy, a process known as myelination occurs in the brain and nervous system. It's how the brain creates its wiring.
Iron is important for myelination, and without it being provided during that period, then myelination may not occur adequately or optimally.
"So once you don't have enough myelination, then you are on the wrong track," Amin says. "And myelination is important for future development. Language development is dependent on myelination. Even motor development is dependent on myelination.
In the first study of its kind, Amin compared brain development in babies of women with and without iron deficiency. He looked at 80 premature babies - half born to women with iron deficiency and half whose mothers were not anemic.
Amin attached electrodes to kin on the foreheads and backs of newborns less than 36 hours old. Using headphones Amin played sounds for the babies. Amin was able to measure how fast auditory impulses passed through the babies' brains. He says this is an indirect way of measuring how well the brain is myelinated.
"We do not have a reliable tool to look for other parts of the brain, but it's more like a window... it provides us an indirect way of evaluating brain maturation," Amin says.
Amin says he was working on the suspicion that iron is required not only for maturation of the nerves associated with the auditory system but also for brain maturation as a whole.
"What we are seeing with the auditory maturation probably is also reflected in the brain maturation," Amin says.
What he found was that in babies born to mothers with anemia, nerve impulses passed more slowly through their brains.
According to the World Health Organization, more than 30 percent of pregnant women in developing countries lack sufficient iron in their blood. So these results have global implications. But there are also issues for mothers in developed countries.
"A lot of maternal conditions such as diabetes, hypertension, even including smoking during pregnancy, can decrease the iron transfer to the babies," Amin says. "So mother may have enough iron in store, but with those conditions, the iron is not able to get to the babies."
Amin says he'd like to continue studying some of these babies to see whether the effects of iron deficiency and slow myelination persist and whether they cause problems as children grow.
Amin presented his findings in a paper given at the Pediatric Academic Society meeting in Baltimore.