The acaryas specifically mention that in this verse the words matuh anugrahat (by the mercy of their mother) refer to the breast milk of their mother. In India it is a common belief that if a baby is fed his mothers milk for at least six months, his body will be very strong. Besides that, it is mentioned herein that all the sons of Agnidhra were endowed with the nature of their mother. Bhagavad-gita (1.40) also declares, strisu dustasu varsneya jayate varna-sankarah: when women are polluted, varna-sankara, unqualified children, are generated, and when the varna-sankara population increases, the entire world becomes hellish. Therefore, according to Manu-samhita, a woman needs a great deal of protection in order to remain pure and chaste so that her children can be fully engaged for the benefit of human society.