http://www.livestrong.com/article/507103-danger-of-oil-of-oregano-during-pregnancy/
About time this is on the web. So, maybe if you ingest the stuff right after sex you can use it as birth control? It is pretty harsh, though. Yes it DOES put you on the rag. Personal experience, though that won't happen again. Thank the gods I'm through with that garbage.
Also, check this out:
http://angryforareason.blogspot.com/2006/02/how-to-induce-miscarriage-herbally-and.html
Does it work? Hell if I know.