An excerpt from this note comes from the thesis “To Trust Man of that Nation”?: Degeneration, James FitzGerald, and Elizabethan Mercy in Ireland by Natalie Sweet
Nursing one’s own infant was just not something that noblewomen did in the 16th century. Certainly, their less-wealthy sisters might have fed their own young, but status demanded a higher standard for the upper echelon of society. Husbands liked their wives’ breasts to remain rounded, and breastfeeding interfered with sex – after all, it was believed in the 16th century that having sex curdled a mother’s milk. Additionally, as breastfeeding acted as a form of birth control, it was a hindrance to producing more heirs. But who, then, was to feed the young?
First of all, it could not be just anyone. Wet nurses were chosen with great care, and often came from the upper middle-sort. They might have several children to feed, or only one. The woman chosen to feed Princess Elizabeth, however, would have only seen to her royal charge’s needs. She was assisted by dry nurses who saw to other matters relating to Elizabeth’s little body, but only she could provide the sustenance and character that was needed to make the princess strong.
Did I mention character? Why, yes, I did. This is because wet nurses were thought to pass down their traits to the children they looked after. Through the milk, Elizabethans believed that children took on the particular physical and psychological traits of their nurses. The fear of outside corruption was so prevalent that hirers discouraged wet-nurses from engaging in intercourse with their husbands during the breast-feeding period for fear that the husband’s traits would also be transferred to the child. This belief extended beyond England, and was acknowledged throughout the early modern world. For example, the Italian humanist Francesco Barbaro implored wives in “On Wifely Duties” to breastfeed their own children since “[t]he power of the mother’s food most effectively lends itself to shaping the properties of body and mind to the character of the seed.” Indeed, he used the example of young goats to make his point, noting that “when young goats are suckled with sheep’s milk their hair becomes much softer, and when lambs are fed on goats’ milk, it is evident that their fleeces become much coarser.” Similarly, “noble women should always try to feed their own offspring so that they will not degenerate from being fed on poorer, foreign milk.” If such a situation could not be avoided, Barbaro suggested children not be given to “slaves, strangers, or drunken and unchaste women” so that “the young infant will not imbibe corrupt habits and words and will not receive, with his milk, baseness, faults, and impure infirmities and thus be infected with a dangerous degenerative disease in mind and body.” Barbaro was not the first person to make these observations, either. He noted that Plutarch, Vergil, and Theocritus had made similar suggestions in their own lifetimes.
Still, decorum and the need for heirs would have trumped theories such as Barbaro’s in Henry VIII’s court. Even if Anne herself wished to nurse Elizabeth, the urgency to produce a son would have likely overridden her desire to take on this motherly task. At best, she would have searched out a woman with those characteristics she hoped that Elizabeth might one day display. Virtue, intelligence, maybe even a courage and spirit that matched Anne’s own personality – these were the traits that Anne would have searched for in Elizabeth’s wet nurse.
 Merry E. Wiesner-Hanks, Women and Gender in Early Modern Europe, Third Edition, (New York, Cambridge: Cambridge University Press, 2008): 92.
 Francesco Barbaro,, “On Wifely Duties,” in The Earlthly Republic: Italian Humanists on Government and Society, Benjamin G. Kohl and Ronald G Witt, ed. (Philadelphia: University of Pennsylvania Press, 1978): 222-223. “On Wifely Duties” was part of a larger work, De re uxoria.
 Ibid., 222-224.