(RxWiki News) Children exposed to as little as half an alcoholic drink a day in utero - even if they didn't have fetal alcohol syndrome - appeared to suffer in their achievement test scores.
Yet the children who were exposed to cocaine, tobacco or marijuana while in the womb did not have lower scores on standardized academic tests compared to their peers.
"Don't drink, smoke or use drugs while pregnant."
Ruth Rose-Jacobs, Sc.D., an associate professor of pediatrics at Boston University Schools of Medicine and a research scientist at Boston Medical Center, led a study looking at how exposure to controlled substances before birth might affect later academic performance.
The researchers looked at academic achievement scores from 119 low-income, 11-year olds from city neighborhoods. The scores were taken from a standard achievement test commonly used to assess academic abilities in research studies.
All the children were already part of a long-term study looking at the impact of intrauterine cocaine exposure and how it does or does not affect children, both on its own and/or combined with exposure to alcohol, tobacco and marijuana.
Eligible children were born on time, did not spend time in the neonatal ICU, did not have symptoms of fetal alcohol syndrome, and did not have exposure to any illegal drugs except cocaine and/or marijuana.
The average number of days that mothers reported for their cocaine use was 21 days. The researchers also tested the levels of cocaine components in the newborn's stool to match the use self-reported by mothers.
The data from the students showed no apparent impact on academic scores for students who had been exposed to cocaine, marijuana or tobacco - but the same was not true of alcohol exposure.
Even after researchers took into account other factors, including other substances the children may have been exposed to, the overall scores on math reasoning and spelling were lower for children who had been exposed to alcohol during their mother's pregnancy.
The alcohol exposure for the lower-scoring children, also self-reported by the mothers, included any exposure of at least half a drink per day on average.
Rose-Jacobs said it was especially significant that children who had been exposed to alcohol had scored lower since they had not been born early and had not been diagnosed with fetal alcohol syndrome - both independent factors for lower academic achievement.
When the children's depressive symptoms were taken into account, however, the relationship between their exposure to alcohol in utero and their lower scores was weakened.
Rose-Jacobs said it was not clear whether the depression these students are experiencing preceded their poor achievement or occurred because of their lower achievement.
The study appears online in the journal Vulnerable Children and Youth Studies. Funding for the researching came form the National Institute on Drug Abuse, the National Center for Research Resources and the National Institutes of Health.