Wet-nurse

A wet nurse is a woman who breast feeds and cares for another's child. Wet nurses are employed when the mother is unable or chooses not to nurse the child herself. Wet-nursed children may be known as "milk-siblings", and in some cultures the families are linked by a special relationship of milk kinship. Mothers who nurse each other's babies are engaging in a reciprocal act known as cross-nursing or co-nursing.

A wet nurse can help when a baby's natural mother is unable or chooses not to feed the infant. Before the development of baby formulas in the 20th century, when a mother was unable to breastfeed her baby, the baby's life was put in danger if a wet nurse was not available. There are many reasons why a mother is unable to lactate or to produce sufficient breast milk. Reasons include the serious or chronic illness of the mother and her treatment which creates a temporary difficulty to nursing. Additionally, a mother's taking drugs (prescription or recreational) may necessitate a wet nurse if a drug in any way changes the content of the mother's milk. There was also an increased need for wet nurses under circumstances when the rates of infant abandonment by mothers, and maternal death during childbirth, were high. Some women choose not to breastfeed for social reasons. Many of these women were found to be of the upper class. For them, breastfeeding was considered unfashionable, in the sense that it not only prevented these women from being able to wear the fashionable clothing of their time but it was also thought to ruin their figures. Mothers also lacked the support of their husbands to breastfeed their children, since hiring a wet nurse was less expensive than having to hire someone else to help run the family business and/or take care of the family household duties in their place. Some women chose to hire wet nurses purely to escape from the confining and time-consuming chore of breastfeeding. Wet nurses have also been used when a mother cannot produce sufficient breast milk, i.e., the mother feels incapable of adequately nursing her child, especially following multiple births. Wet nurses tend to be more common in places where maternal mortality is high.

A woman can only act as a wet-nurse if she is lactating. It was once believed that a wet-nurse must have recently undergone childbirth. This is not necessarily true, as regular breast suckling can elicit lactation via a neural reflex of prolactin production and secretion. Some adoptive mothers have been able to establish lactation using a breast pump so that they could feed an adopted infant.

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