Let's start with a short history lesson: Ingesting someone else's breast milk, or "wet nursing", (also called cross-nursing) is still very much alive in many cultures throughout the world. However, in Western cultures it has been fairly uncommon since the 1930s. In the past, feeding someone else's baby simply required that the nursing woman was healthy, had no infections, and wasn't taking any medications. With the advent of HIV/AIDS, things changed dramatically. Women were still performing the act of wet nursing, but HIV testing both mom and baby became essential. This was (and still is) set up by private arrangement. Hospitals and doctors do not take on this task.
Cross-nursing is often used by women who are attempting to create a strong milk supply when their own babies can't nurse (premature or sick). Having a healthy baby nursing at the breast will do just that. Also, women who are adopting and wish to breastfeed will cross-nurse to stimulate milk supply. As long as proper infection precautions are observed, this is an excellent option. The cross-nursing mom should be healthy and well-nourished; should not have any infections; should not take any medications; and not smoke.
So, are there dangers to wet or cross-nursing? As with any intense decision like this, the following should be considered:
- Potential for infection (mom or baby)
- Interruption of milk supply for the mother's own baby
- Composition of milk will be different if the babies are different ages or at different stages
- Mom may have problems letting-down
- Baby may refuse to nurse (if older than four months)
- Negative impact on siblings and/or the household
Lawrence RA, Lawrence RM. Breastfeeding: A Guide for the Medical Profession. Mosby.