Mental retardation and mother's hypertension during pregnancy.

A comparison of the history of hypertension in the mother during pregnancy was made between a group of 136 mentally retarded children and a randomly selected control group of 122 children. The cases and the controls were 9 or 10 years of age at the time of the survey. A number of potentially confounding factors were controlled for in a multiple logistic model. Maternal hypertension during pregnancy was associated with a relative risk of mental retardation in the offspring of 6.1 with 95% confidence interval of 1.3-28.9.