Long-term outcome of prenatal treatment of congenital adrenal hyperplasia.

Prenatal treatment of congenital adrenal hyperplasia (CAH) with dexamethasone to minimize the genital virilization of external genitalia of affected girls has been in use since the mid-1980s. The positive effect of reducing virilization is now established. However, experimental data from animal studies and observations on adverse medical events in human newborns have raised concerns about the long-term safety of the treatment. Most animal studies on prenatal treatment with synthetic glucocorticoids have been designed to mimic treatment for lung maturation in preterm infants. The primary focus has been on a possible impact on fetal programming and the development of the metabolic syndrome with insulin resistance, type 2 diabetes, and high blood pressure. Altered reactivity to stress as a function of differences in reactivity of the HPA axis and glucocorticoid receptor function have been assayed. Effects on cognition, especially memory, have been observed. In children at risk for CAH and treated prenatally with dexamethasone, no overall effects on full-scale IQ have been observed, but a negative effect on verbal working memory has been reported. Contradictory effects on social behavior with respect to shyness and inhibition have been discussed. There is an urgent need for in-depth studies of long-term outcome in prenatal treatment of CAH regarding both maternal side effects and possible negative metabolic as well as cognitive and behavioral effects in the growing fetus and the child in her development into adulthood.