"used to ease symptoms of premenstrual syndrome (PMS) as well as to regulate menstruation. Though it contains no hormones, it appears that chasteberry can affect hormonal activity by stimulating the pituitary gland to decrease production of prolactin, a hormone involved in milk production. The reduction in prolactin can help to alleviate breast tenderness and other discomforts associated with PMS.
Chasteberry also appears to affect levels of luteinizing hormone (LH) and progesterone, other reproductive hormones that may contribute to symptoms related to the menstrual cycle. Chasteberry appears to be useful in reducing the irritability, bloating and depression that many women experience right before their menstrual periods begin. For that reason, it is finding its way into the formulations of some "just for women" fat burners -- see the SlimQuick review for details."
if it works for women to stimulate the pituitary and increase LH production it could be used in PCT. it might also help with prolactin gyno.