The change towards a prestigious variation of a language, according to  sociolinguistics research reports, is most commonly headed by women. Nevertheless, few studies report the influence that women’s linguistic behavior has on the maintenance or shift of an indigenous language in opposition to the prestigious language. The intention of this article is to analyze the role that the indigenous woman plays on the maintenance or shift of her first language. 
             The hypothesis that guides this research is that the role of the indigenous woman changes in different linguistic communities depending on the language shift stage and that the women’s linguistic behavior can be an indicator of the language shift degree. Two Mexican indigenous languages have been considered for the object of this study, the Mixe of Oaxaca and the Náhuatl of the State of Mexico.
       On one hand, in the case of the Mixe in Oaxaca, the information reveals that the Mixe woman appears as a protagonist in the maintenance of her language as she prefers it to be the familiar language and to transmit it to her children. In this linguistic case, in contrast to the men,  women do not stand out as the innovative ones of change, women still assume a more conservative position on the language in comparison to men. Thus, the degree of shift is primarily for the case of the Mixe language. On the other hand, in the case of the Náhuatl in the South of the State of Mexico, the information reveals that the woman influences the Náhuatl language shift in a definitive way, as she does not transmit the indigenous language to her children, and in contrast to men she only uses her first language to a minor degree. Therefore, we have a community in an advanced stage of linguistic displacement.  
        The information that we present here offers the first evidence of the key role that women’s linguistic behavior plays on the language shift and how this can be an important indicator of the degree of language vitality