Ruling on milk banks
Question

                In America there are banks
      known as milk banks, which buy milk from nursing mothers then sell it to women who need to
      give it to their children but their own milk is lacking, or they are sick or are too busy
      working, etc. What is the ruling on buying milk from these banks?
Praise be to Allah.We put this question to Shaykh Muhammad ibn
    Saalih al-‘Uthaymeen, may Allaah preserve him, who replied as follows:
This is haraam. It is not permissible to establish this kind
    of bank, because this is human milk, and the milk from different mothers will be mixed, so
    that no one will know who is the mother. In Islam, drinking the milk of a woman creates
    the same relationship as does a close tie by blood (i.e., it has an effect on whom one may
    and may not marry, etc.). If the milk is of any kind other than human, then there is
    nothing wrong with milk banks.
And Allâh knows best.