Language lateralization and handedness in women prenatally exposed to diethylstilbestrol (DES)

Hand preferences and language lateralization were assessed in women exposed prenatally to the synthetic estrogen, diethylstilbestrol (DES), and in the ir unexposed sisters. The DES-exposed women showed an increased degree of h and preference (regardless of direction) and were more likely to be left ha nded for writing. However, the groups did not differ significantly on a dic hotic Listening measure of language lateralization. Perhaps as a result of the alterations in hand preferences, the typical relationship between hand preferences and language lateralization was disrupted in the DES-exposed gr oup. Also, within the DES-exposed group, exposure early in gestation correl ated with left handedness whereas exposure late in gestation correlated wit h reduced left ear (right hemisphere) scores on the verbal dichotic task. R esults are discussed in terms of theoretical perspectives predicting hormon al influences on sexual differentiation of hemispheric asymmetry and in ter ms of separate critical periods for hormonal effects on individual sexually differentiated characteristics. (C) 2000 Elsevier Science Ltd. All rights reserved.