Queen Anne's Lace ... What?

I was browsing a wildflower book and came across this: the seeds of the dainty Queen Anne's Lace were used as a morning-after contraceptive! Wow, how did settlers know stuff like that?

I looked it up in Wikipedia and sure enough: The crushed seeds were once thought to be a form of birth control ... first described by Hippocrates over 2,000 years ago. Research conducted on mice has offered a degree of confirmation for this use—wild carrot was found to disrupt the ovum implantation process, which reinforces its reputation as a contraceptive. Chinese studies have also indicated the seeds block progesterone synthesis, which could explain this effect.

Don't try this at home though! Queen Anne's Lace (aka wild carrot) resembles the deadly poison hemlock!