FRIDAY, Oct. 23, 2009 (HealthDay News) -- While adult male monkeys exposed to cocaine in the womb have poor impulse control, the same is not true for female monkeys, new research has found.
The male monkeys continued to have poor impulse control 15 years after birth. Impulsivity is a risk factor for drug abuse, said the researchers, who added that their findings could help improve understanding of human drug abuse.
"This is the first time that so many different measures of impulsivity, which is considered a risk factor for drug abuse, have been looked at in the same group of animals," lead investigator Lindsey Hamilton, of Wake Forest University School of Medicine, said in a university news release.
"We're looking for ways to predict which individuals are going to take drugs during their lives. It was very surprising to see that, even more than a decade after the prenatal cocaine exposure, the monkeys ended up being more impulsive and possibly more susceptible to drug use. It was particularly interesting, however, that this effect was only seen in the males. Something is either protecting the females from the effects of the cocaine exposure in the womb or making the males more susceptible to the lasting effects," Hamilton explained.
Hamilton and colleagues conducted four impulse control tests with male and female monkeys exposed to cocaine in the womb and monkeys with no cocaine exposure.
"The fact that we are seeing differences at all is particularly striking because this is 15 years after the monkeys were exposed in the womb to cocaine. Fifteen years is the equivalent of middle age for monkeys. The fact that fairly large differences are still turning up is fascinating," Hamilton added.
The study was scheduled to be presented Oct. 21 at the annual meeting of the Society for Neuroscience, held Oct. 17 to 21 in Chicago.
There are an estimated 7.5 million children in the United States who were exposed to cocaine while in the womb, and 30,000 to 160,000 infants born each year have been exposed to cocaine in the womb, according to the federal government and previous research. The effects of this exposure on child development aren't clear.
"Whether or not these children who were exposed to cocaine in the womb may be more vulnerable to drug use is a timely question, both because these children are now young adults, a time when a lot of drug experimentation occurs, and because cocaine abuse among young women of childbearing age is a growing problem in this country," Hamilton noted.
The March of Dimes has more about illicit drug use during pregnancy.