This study is the first to document the negative effects on cognitive development in a scientifically rigorous manner. Singer, professor of pediatrics and psychiatry, and interim provost and CWRU vice president, said the study was unique because it had measures of both the mothers self report of their drug use prenatally, as well as infant meconium, which provided a physical measure of the amount of drug exposure. The study also controlled for many more factors in the environment than prior studies, including stimulation levels in the home, mothers vocabulary and mental health status and characteristics of foster caregivers. The team used newly standardized versions of the major infancy development tests. And they were able to maintain more than 90 percent of the participants during the study, and at two years, 100 percent of the sample had at least one follow-up visit.
Mothers and infants were recruited between 1994 and 1996 from a high-risk population screened for drug use. Urine samples were obtained immediately before or after labor and delivery, and analyzed for the presence of cocaine metabolites, cannabinoids, opiates, PCP and amphetamines. Urine tests for drugs were performed by the hospital on all women who received no prenatal care, appeared to be intoxicated or taking drugs, had a history with the Department of Human Services in previous pregnancies, or self-admitted or appeared to be high risk for drug use after interview by hospital staff. Meconium was collected in the hospital from infants diapers and screened for drugs.
Researchers initially identified 647 mothers and infants for the study, excluding 232 for various reasons. Infants were seen at the research laboratory at 6.5, 12 and 24 months and administered the widely used Bayley Mental and Motor Scales of Infant Development (BSID II) standardized assessments. The scales assigned infants a s
Contact: George Stamatis
Case Western Reserve University