The first contender for the title ‘Sai Ma’ (i.e. “Mother Sai” or also “mother of Sai” was a Mrs. Nareng. Her claims have been definitively rejected by Sathya Sai Baba through his editor, V.K. Narasimhan, in the journal Sanathana Sarathi as can be seen below.
An Australian devotee who lived around the Sai Baba ashrams and wrote a book Little Heart, Unique Graciousness, Prasanthi Nilayam, Saindra, 1994, with “mystical visions and conversations reported by an elderly English lady who claims to have been Radha’s brother in a previous incarnation.” This woman hung around Sai Baba ashrams, living outside and never getting his attention or interviews. She compensated by claiming a “inner view” vouchsafed by Sai Baba himself. He never gave the slightest sign that he accepted her claim. She gathered all the followers of Sai Baba she could, pretending to be able to give spiritual messages and advice, as has been the case of many such bogus ‘channelers’ of Sai Baba (who firmly, repeatedly and most strongly denied he has any mediums or spokespersons whatever).
Another contender for the title ‘Sai Ma’ (also spelt Sai Maa) is French citizen Chalander Sai Ma (see here) who was a devotee of Sathya Sai Baba (hence the ‘Sai’ in her name, a name not used before Sai Baba of Shirdi introduced it). She is reportedly involved with methods promoted by Deepak Chopra and endorses indoctrination into the usual doubtful and unsupported Hindu guru speculations about self-realization, such as represented in the West by the insufferable book ‘A Course in Miracles’. She is promoted as a blessed Indian saint, and does seem to do good humanitarian work, apart from the obvious doubtfulness of any claim to sainthood (usually only self-professed, then taken up by some followers).