A couple of quotes. One from the lady I mentioned below
"Do not take this. I did, against all advice and it gave me a 142 day cycle!!
Its a very strong herb and shouldn't be used unless done so under the supervision of an expert.
Search the threads and you'll find other people with horror stories. Also agnus castus won't increase your chances of getting pregnant. it doesn't make you more fertile."
"AC can in some cases make hormonal imbalances worse.
It can be a bad idea to self medicate with AC: if you really want to take this you should only do so following the advice of a medical herbalist."