Green’s Dictionary of Slang

the vagina; thus unwemmed adj., lacking a vagina.

1660		Wandring Whore I 14: For broaching a belly unwemmed and unboared.
1674–80		‘The Cumberland Lass’ in Farmer Merry Songs and Ballads (1897) I 156: Then I embrace’d this lovely Lass, / And strok’d her Wem so bonnily.
1684		‘The Scotch Lass Deceived’ in Henke Gutter Life and Lang. (1988) 283: He got in a gude merry Mude, / he thought it was time then to be Rude; / He kindly stroakt my Downy Wem, / And farther proceeded, O then, O then.
1700		‘The Cumberland Lass’ in Playford Pills to Purge Melancholy II 135: Then I embrac’d this lovely Lass, / and stroak’d her Wem so bonnily.
1707		Fifteen Plagues of a Maiden-Head 5: I’ll be thus plagu’d, and live in daily Misery / Till some Spark shall rummage all my Wem about.