I dont have all the info since the product is not released yet, but .....
A study has found that treatment of 20 healthy men with higher doses of Vitex Agnus-castus was associated with a slight reduction of prolactin levels, whereas lower doses caused a slight increase as compared to doses of placebo.[8] A decrease of prolactin will influence levels of Follicle-stimulating hormone (FSH) and estrogen in women; and testosterone in men.
http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&list_uids=9021345&dopt=Abstract
It is used in some supplements for male bodybuilders as a secondary component because of its effects on testosterone levels