OK so here's A.L. Lloyd's version, from the CD The Bird and the Bush: Traditional Songs of Love and Lust

PRETTY POLLY
(as sung by A.L. Lloyd)

Pretty Polly, pretty Polly, it's I've come a-wooin';
Pretty Polly, pretty Polly, it's I've come a-wooin'.
She says, "Creep and crawl through the window, And let's get doin'
And lay your leg over me, over me, do.

Oh, me britches is tight and I cannot undo 'em,
Me britches is tight and I cannot undo 'em;
There's a knife on the window sill, love, take it to 'em,
And lay your leg over me, over me, do.

Well the knife it was got and the britches cut asunder,
The knife it was got and the britches cut asunder;
And then they went to it like lightning and thunder,
Cryin' lay your leg over me, over me, do.

About forty weeks after, the fine baby come bawlin',
About forty weeks after, a fine baby come bawlin';
But she never regretted that creepin' and crawlin',
And cryin' lay your leg over me, over me, do.


transcribed by ear from the CD The Bird and the Bush: Traditional Songs of Love and Lust