Chaste tree (Vitex agnus-castus), also known as chasteberry, has a long history of traditional use, particularly in Europe, for supporting women’s reproductive health. Modern scientific studies have provided evidence that chaste tree may benefit the uterus primarily by influencing hormonal balance, especially with respect to the menstrual cycle and associated symptoms. The active compounds in chaste tree are believed to act on the pituitary gland, reducing prolactin levels, and thereby supporting the luteal phase of the menstrual cycle. This hormonal modulation can positively affect symptoms of premenstrual syndrome (PMS) and some menstrual irregularities, which are linked to the function of the uterus.

Several clinical trials have shown that chaste tree extract can reduce symptoms of PMS, such as breast pain, mood swings, and menstrual irregularities, which are often related to hormonal imbalances affecting the uterus. For example, a systematic review published in 2017 in the journal Phytomedicine concluded that Vitex agnus-castus was superior to placebo in relieving PMS symptoms in several randomized controlled trials. The herb is also used to address mild cases of hyperprolactinemia and some menstrual disorders, although more research is needed for conditions like endometriosis or fibroids.

In summary, scientific evidence supports the use of chaste tree for hormonal regulation that can benefit the uterus, especially for PMS and certain menstrual irregularities, though its effects on structural uterine conditions are less well established.