Data derived from the Southern Youth Study (a six-year, three-wave study of rural youth and young adults) were utilized to examine a version of the Attitudinal Behavioral (A-B) Dimension of the Social Mobility-Fertility Hypothesis wherein it was posited that orientations for upward social mobility would have negative effects upon subsequent early fertility among a panel of 527 females. Racial and socioeconomic class comparisons were made to determine if the effects of social mobility orientations operated differentially on the early fertility of the white lower class vs the white middle class and of the white lower class vs the black lower class. The variables employed were: levels of occupational and educational aspiration; intergenerational occupational and educational mobility; breadwinner's occupation; educational level of mother; and fertility. Results indicated: there were class and racial differences in the effect of education for self and occupation for mate on subsequent fertility; the effects of mobility orientations were the same as those of the aspiration measures but were not significant; the hypothesis was most consistently supported among the white lower class; both educational and occupational aspirations for mate were significantly related inversely to fertility among seniors; there were similarities in the white middle class for educational but not for occupational aspirations for mate and high educational but only middle range occupational aspirations for the black lower class. (JC)