Background: In the present study we analyzed the relationship between home environment and cognitive abilities in small-for-gestational-age infants.
Method: A group of 142 small-for-gestational-age infants and a control group of 172 appropriate-for-gestational-age infants were tested on the Fagan Test of Infant Intelligence at 7 months. The Home Screening Questionnaire was completed by the mothers when their infants were 13 months.
Results: The group of small-for-gestational age infants had significantly lower scores on both the Fagan test (p < 0.05) and on the Home Screening Questionnaire (p < 0.01). A significant relation between the Fagan test score and the home score was found for the small-for-gestational-age group (p < 0.05). When the home score was controlled for, the difference in mean Fagan score between the two groups of infants disappeared.
Conclusions: It is suggested that small-for-gestational-age infants may be more vulnerable to adverse social conditions that infants born with a normal birthweight for gestational age. Results also suggest that cognitive impairments among small-for-gestational-age infants may be an effect of their social environments and their parents' general intelligence. Possible physical and neurological effects of intrauterine growth retardation may be less important for cognitive functioning.