There are several things that may make John Donne's poem, "The Flea," uniquely English, and these come in the form of the young woman's resistance against having sex outside of wedlock. Donne points out her concerns in his poem:
Thou know’st that this cannot be said
A sin, nor shame, nor loss of maidenhead...
These lines reflect the young woman's concerns in guarding her virtue: her virginity and her reputation—
She has rejected his advances, remonstrating that sex for them would be a sin, a shame, and, for her, a loss of virginity—strong traditional arguments in seventeenth century England.
The aspects of the reasons for her refusal are hallmarks of elements of good breeding among young ladies at the time that would guard against scandal, which would essentially make them undesirable as wives. A hint of scandal created an irreparable blemish on a young, unmarried woman's character and basically destroyed her prospects to marry well. While men could have lovers prior to marriage, a woman's reputation was expected to be above reproach. Things had not changed greatly even into the 18th Century:
Women...were more governed by their emotions, and their virtues were expected to be chastity, modesty, compassion, and piety.
Traditional to English norms, this poem is uniquely English in the expectations society had for young, unmarried women, quite different than those it had for young men. Poems such as this are not at all unusual, as seen in Herrick's "To the Virgins, To Make Much of Time," and Marvell's "To His Coy Mistress." These are a few examples of English poetry written by men trying to convince a young woman to throw aside her code of maidenly behavior in light of persuasion by lusty and convincing suitors.