Researchers look at impact of nicotine on babies

(PROUNOUNCER: "Espy" is "ESS-pee.")

CARBONDALE, Ill. -- A Southern Illinois University Carbondale neuropsychologist has received a $1.78 million federal grant to look at how prenatal tobacco exposure might affect babies' later development.

"We know that mom's smoking during pregnancy influences baby's birth weight and whether or not baby is born full term," said Kimberly Andrews Espy, an associate professor of family and community medicine in SIUC's School of Medicine.

"What we don't know is how that impacts baby's behavior."

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With the help of Carbondale neonatologist Rudolph Foy and local obstetricians, who will recruit many of the nearly 400 pregnant women and babies needed for the project, Espy and veteran tobacco researcher David G. Gilbert from SIUC's psychology department are beginning a five-year study of nicotine's effects on such traits as growth, motor skills and temperament.

Project consultants Marilyn L. Riese, a University of Louisville researcher specializing in infants, and Anne L. Wright, a University of Arizona tobacco specialist, will help with assessing the babies and measuring prenatal smoking.

Funding, in annual payments of $357,000, comes from the National Institute of Drug Abuse, a National Institutes of Health member.

Identifying and obtaining new sources of grant funding and providing outreach services to the region are among the goals of Southern at 150, the blueprint for the long-range growth of the University.

Espy, whose earlier research in Kentucky and Arizona focused on cocaine use in pregnancy, said she decided to switch directions in her work shortly after coming to SIUC in 1996.

"Partly that was because you don't see a lot of heavy drug use in this area -- I'd have been waiting to complete a project like this until I was 80 if I'd stayed with cocaine," she said.

"But it's also a natural transition because tobacco is a lot like cocaine. It's very addictive, and it works on similar areas in the brain. And because this is a rural environment, as opposed to the urban environments where I was before, you can get a relatively clean sample of smokers who are just smokers and not heavy drug users, too. We can look specifically at tobacco without worrying about the effects of these other substances on brain and behavior."

Although pregnant women use tobacco more than any other drug, scientists know remarkably little about how it affects their babies.

"It's been very neglected as a source of study because it's a legal substance," Espy said. "In fact, 40 years ago many physicians used to encourage women to smoke during pregnancy because it was thought to reduce morning sickness.

"And then, too, smoking during pregnancy is not like drinking alcohol, which can lead to the kind of deformities seen in fetal alcohol syndrome. There's the thought, 'Well, baby looks normal, so it must be fine.'"

But animal tests have shown that all is not fine when a fetal nervous system comes in contact with nicotine. Some cells don't develop according to plan, some don't develop at all, and some of their signaling systems are thrown out of whack.

As most of this disruption takes place in parts of the brain that in humans link up with muscle control, mental concentration and general disposition, Espy thinks there's reason for concern -- especially if that developing human is born early.

"Babies who are born early, especially those who are born very early (three months or so), are at risk for subtle differences in attention and emotional regulation to begin with -- how much they cry, how much they sleep, how irritable they are, how soothable they are," she said. "Because of that vulnerable nervous system, prenatal tobacco exposure might make things worse.

"On the other hand, if they're born early, they are exposed to less tobacco prenatally than full-term babies are, and they're usually kept for some time in hospital units where they're not exposed to environmental smoke during critical times for brain development. Full-term babies often go home to second-hand smoke, because if mom smoked during pregnancy, she's likely to smoke afterwards. So maybe the preemies would do better. That's one thing we'll be looking at in our study."

Researchers will interview both smoking and non-smoking moms-to-be and analyze their urine in the fourth and seventh months of pregnancy and again right after they deliver their babies. They'll also study the babies at birth, at two weeks of age and at four weeks, looking at how the babies are growing, developing and behaving and comparing what they observe with the chemical content of the babies' urine.

Espy expects the study's outcome could help smoking mothers to stop -- at least while they're pregnant.

"Prenatal tobacco exposure is the single largest preventable risk factor for low birth weight and prematurity, but for a lot of moms, that's not a big thing -- they may even think, 'Well, good! A smaller baby will be easier to deliver,'" Espy said.

"But if we can say, 'Babies whose moms smoke during pregnancy cry more often, cry in a more high-pitched way, are more difficult to soothe' and so forth, that could help motivate them to do something that is, after all, quite difficult. And that would not only help them and their babies, but would improve public health overall."

CAPTION: Target practice -- In her lab at Southern Illinois University Carbondale, neuropsychologist Kimberly Andrews Espy demonstrates on a doll one method of testing a new baby's ability to respond. Most newborns show interest in the stark contrast of black and white by "stilling" (they stop wiggling around), "brightening" (their eyes widen, and they look like they're paying attention) and "tracking" (their heads move as their eyes follow the bulls-eye). Espy plans to test some 400 babies as part of a five-year, $1.78 million federal grant focusing on the effects of prenatal tobacco exposure.

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