WASHINGTON (AP) - Experiments in rats indicate that a mother's use of the drug ecstasy during pregnancy can result in learning and memory problems for her offspring.

The finding published in the May 1 issue of the Journal of Neuroscience is the first evidence for specific memory damage associated with a mother's use of ecstasy, the National Institute on Drug Abuse reported.

"These findings suggest that (ecstasy) may pose a previously unrecognized risk to the developing brain," causing long-term learning and memory problems, according to the team led by Charles V. Vorhees of Children's Hospital Research Foundation and the University of Cincinnati College of Medicine in Cincinnati.

The scientists administered the increasingly popular drug, also known as MDMA, twice a day to newborn rats either on the first 10 days of their lives or on days 11 through 20 of their life. They reported that the exposure to the rats' still-developing brain at this time was equivalent to exposing a human to the drug either early or late in the third trimester of pregnancy.

Thus, the team concluded, their results "raise concerns about the safety of MDMA when exposure occurs during stages of brain development analogous to the human fetal period."

Vorhees' team found that rats given the drug on days 11-20 suffered from impaired learning and memory in maze tests. The damage was long-term, persisting even after the rats reached adulthood.

However, those exposed on the first 10 days showed almost no effects.

Exposure to the drug had no effect on survival, the team said, but it did affect weight gain. After the drug was stopped, the rats recovered to about 90 percent of the weight of rats not given the drug.

Recent reports have shown that ecstasy use is dramatically increasing in the United States, Europe and Southeast Asia.

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