Objective: To examine the effects of prenatal alcohol exposure ascertained prospectively on infant visual acuity across a range of exposures and factors that mediate or moderate these effects.
Study design: Infant visual acuity was examined in 131 Cape Coloured (mixed ancestry) maternal-infant pairs in Cape Town, South Africa. Drinking patterns were documented by maternal reporting during pregnancy. Grating acuity was assessed with Teller Acuity Cards (TAC) at 6.5 months after term. Data were analyzed by correlation, multiple regression, and analysis of variance.
Results: Greater average daily prenatal alcohol exposure was related to poorer acuity, as indicated by lower TAC scores. The effect of alcohol on acuity was significant primarily for infants born to mothers > or =30 years of age at delivery, in comparison to infants born to younger mothers. This effect was not mediated by gestational age or birth size or attributable to alcohol-related neurocognitive deficits.
Conclusions: This study linked prenatal alcohol exposure ascertained prospectively to poorer visual acuity in infancy. The results are consistent with clinical and animal evidence of alcohol-related disruption of the visual system.