If the subject is herbs in folk ballads, there's a definite abortifacient in Tam Lin, a ballad that's full of magic:

Out then spoke her mother dear,
And ever alas, said she,
I know an herb in the merry green wood
That will scathe thy babe from thee...

She had not pulled at Cartershay
An herb but barely one,
Til up there started young Tamlin,
Said, Leave the herbs alone

Why pulls thou that bitter herb
Among the leaves so green?
And all to kill the bonnie babe
That we got us between

Plunging us, as iot were, into contemporary headlines with a bang.