From the "encyclopedia of adoption":
A small number of adoptive mothers choose to nurse their infants, and it is possible to induce lactation in a woman who has never borne children or never been pregnant. Even if an adoptive mother produces a tiny amount of milk or no milk at all, the tactile closeness to her infant is a very positive experience for many mothers.
The baby's sucking at the breast will further stimulate the production of milk. In some cases, the adoptive mother may have breast-fed biological or adopted children previously. She will need to "relactate" for her new baby.
If the adopting mother knows weeks or months ahead of time that the baby will be arriving, she may opt to use a breast pump to begin stimulating the breasts to induce a milk supply.
