Prenatal exposure to alcohol alters the light response in postnatal circadian rhythm.

We studied the effect of prenatal exposure to alcohol on later circadian rhythm in the rat. In the normal light-dark cycle, an 8-h phase advance brought forward the deep body temperature rhythm in control rats, although it had a smaller effect in prenatally ethanol-exposed rats. In long constant darkness, the phase response of the deep body temperature rhythm to a light pulse at the early subjective night was less marked in ethanol-exposed rats in comparison to controls. These results indicate that prenatal exposure to alcohol has a long-lasting effect on the light responsiveness of the deep body temperature circadian rhythm.