LOS ANGELES, CA (Catholic Online) - The behavior differences found in the test subjects, such as anxiety, depression, moodiness - weren't huge, but lead researcher Linda LaGasse called them "very worrisome."

Meth babies have similarities to so-called "crack babies" - smaller in size and prone to drowsiness and stress. Results in long-term studies conflict on whether children of cocaine-using mothers have lasting behavior problems.

Whether problems persist in young children of meth users is unknown. LaGasse says that methamphetamine has stronger effects on the brain, so it may be more likely to cause lasting effects in children.

The research was published in Pediatrics. The National Institutes of Health paid for the research, including a grant from the National Institute on Drug Abuse.

The most recent data suggests that more than 10 million Americans have used meth, but fewer than one percent of pregnant women are users.

Joseph Frascella, who heads a behavioral division at the National Institute on Drug Abuse, says the research is among "groundbreaking" studies examining effects of substance abuse during pregnancy - but because the study is a first, the results should be viewed cautiously and need to be repeated.

The study of children tracked from age 3 through 5 builds on earlier research by LaGasse on the same group. Mothers were recruited shortly after giving birth in four major U.S. cities.

They were then asked about prenatal meth use and newborns' stools were tested for evidence of the drug. Effects in children exposed to the drug were compared with those whose mothers didn't use meth. However, both groups were high-risk children, with many living in disadvantaged homes.

At the age of 3, scores for anxiety, depression and moodiness were slightly higher in meth-users' children. These differences persisted at age 5. The older children who'd been exposed to meth also had more aggression and attention problems similar to ADHD, attention deficit hyperactivity disorder. Mothers were asked about symptoms, but not if their kids had ever been diagnosed with behavior disorders.

More tellingly, more than half of the mothers who'd used meth during pregnancy also used it afterwards. These women also were more likely to use other drugs during and after pregnancy and to be single mothers. But the researchers said accounting for those differences and others in the two groups' family lives didn't change the results.

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