Abstract 174

Background: Maternal cigarette and alcohol consumption effect the fetal nervous system. Habituation is a sensitive indicator of central nervous system functioning. This study investigated the habituation performance of fetuses at 32 weeks of gestational age.

Subjects: The habituation performance of 137 fetuses was examined. Fetuses were divided into 4 groups: Fetuses exposed to cigarettes and alcohol(n=42); fetuses exposed to alcohol only (n=22); fetuses exposed to cigarettes only (n=21); and fetuses of abstainers (n=52).

Measurements: 4 measures were recorded: 1) Number of trials to habituate, 2) Habituation pattern, 3) Average response latency, 4) Dishabituation.

Results: Maternal alcohol consumption and smoking influenced habituation performance. Fetuses exposed to alcohol and/or cigarettes took longer to habituate than fetuses of abstainers, p<0.05, and displayed an irregular habituation pattern, p<0.05.

Conclusions: Fetuses exposed to maternal smoking and alcohol perform poorly on habituation tasks, suggesting an insult to the developing central nervous system.