October 19, 2005
Study shows that prenatal exposure to alcohol may cause visual problems in infants
Fetal alcohol syndrome (FAS), a disorder that is indicated by distinct facial characteristics, growth retardation, and poor intellectual and attentional function, can occur when mothers drink alcohol heavily during pregnancy. A new study in the October issue of The Journal of Pediatrics shows that prenatal alcohol exposure can also affect an infant's visual acuity or sharpness of vision.
Sandra W. Jacobson, Ph.D. and colleagues from Wayne State University and University of Cape Town evaluated 131 infants of mixed ancestry in Cape Town, South Africa. After interviewing each mother to ascertain her alcohol consumption during pregnancy, the authors tested the visual acuity of the infants at 6 Ã½ months of age using the Teller Acuity Cards (TAC) Test, which is comprised of gray cards with a concentration of vertical black and white stripes on the left or the right side. An examiner looked through a peephole in the center of the card to determine where the infant was looking. Poor visual acuity was indicated when the infant was not looking at the side containing the lines.
Of the infants examined, 22 met the criteria for being diagnosed with FAS, and their visual acuity was significantly poorer than those without FAS. 27% of the infants with FAS scored below the fifth percentile, as opposed to the 9% of the infants without FAS. However, half of the infants with low TAC scores who did not meet the criteria for full FAS were born to mothers who reported binge drinking (greater than 5 drinks per occasion) during pregnancy.
The authors also found that the infants born to mothers ages 30 and older who drank during pregnancy were at greater risk for poor visual acuity, although the older mothers did not drink larger quantities of alcohol. The authors speculate that this could be attributed to the age-related physiological changes in older mothers or to chronic drinking over a longer period of time.
The authors point out that in-depth, ophthalmologic evaluations of the study infants throughout childhood are necessary to determine the extent of visual abnormalities due to prenatal alcohol exposure.
The study is reported in "Effects of prenatal alcohol exposure on infant visual acuity" by R. Colin Carter, MD, Sandra W. Jacobson, PhD, Christopher D. Molteno, MD, Lisa M. Chiodo, PhD, Denis Viljoen, MD, Joseph L. Jacobson, PhD. The article appears in The Journal of Pediatrics, Volume 147, Number 4 (October 2005), published by Elsevier.
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