Does vitex (chasteberry) really have fertility benefits?

What is vitex?

Vitex is a dried fruit that's used in herbal medicine, often to treat hormonal conditions. Its botanical name is Vitex agnus castus, and common names include chastetree, chasteberry, and monk's pepper. (Monks reportedly once used it to tamper their sexual urges.)

There are many species of vitex, but agnus castus is the one usually used in herbal medicine. It's available as a tincture, in capsules or tablets, or ground to add to food. The berries can also be soaked in hot water and drunk as a tea.

Vitex doesn't contain hormones, but some studies suggest it may help regulate hormone levels by acting on the pituitary gland in the brain. Its active components are flavonoids, glycosides, and essential oils.

Are there benefits to taking vitex?

Researchers are studying whether and how vitex might help with a number of conditions, many of which involve the balancing of a woman's hormonal system.

We don't have a lot of conclusive evidence, but so far chasteberry has been shown in clinical studies to help with some bothersome hormonal conditions, including:

• Premenstrual syndrome (PMS)
• Premenstrual dysphoric disorder (PMDD, a more severe form of PMS)
• Abnormal menstrual cycle (which may affect fertility)

Do providers have to prescribe vitex?

You don't need a prescription to take vitex, but it's a good idea to work with your healthcare provider. Not all herbal products are the same (in terms of amounts of active ingredients, purity, etc.), and you'll want to make sure you get the proper dosage if you do decide to try it. Vitex may also interact with some other medications (see risks, below).

Keep in mind that you may need to take chasteberry for months before you experience its effects on your hormones. (It may take as long as six months to regulate a menstrual cycle.) To treat lack of menstruation, your practitioner may recommend taking it for a period of time – say 12 to 18 months – and then taking a break. (You also need to stop taking it if you become pregnant.)

Can taking vitex for fertility really help?

We don't know for sure, but there's reason to believe taking vitex may help with some fertility issues. It may depend on the reason for the infertility, but abnormal hormone levels (and an irregular menstrual cycle) often play a role, and vitex has shown to help with that in some studies.

The herb has been shown to help raise progesterone levels and lower prolactin levels, both of which may help with fertility in some women. In addition, boosted progesterone levels may in some cases help prevent miscarriage.

A review of 43 studies published from 1997 to 2016 concluded that Vitex agnus-castus is beneficial in treating infertility disorder in both men and women (as well as the treatment of PMS). The researchers hypothesized that chemical compounds in the plant influence the pituitary gland, which in turn decrease prolactin. Decreased prolactin can affect the levels of follicle-stimulating hormones (FSH) as well as estrogen in women and testosterone in men.

A 2019 study of 189 women with menstrual disorders showed that treatment with an herbal supplement containing vitex, maca (Lepidium mayenii), and folate helps regulate the menstrual cycle, stimulates ovulation, and increases the chances of getting pregnant. Ovulation increased from 10 percent to 43 percent in the subjects during the six-month period of the study, with no side effects reported. Seventy of the subjects became pregnant during the study. The study also showed a decrease of PCOS from 38 percent to 14 percent (26 of the patients instead of 71).

What are the risks of taking vitex?

There are no studies on the long-term effects of taking vitex, but it seems pretty well tolerated short term. Possible side effects include:

• Stomach upset
• Itchy skin with mild rash
• Headache
• Increased acne
• Heavy menstrual flow

The effects of vitex on pregnant and breastfeeding women haven't been studied, but we do know that it affects the hormonal system (and may suppress lactation). To be safe, don't take the herb during pregnancy or while nursing.

Vitex can interact with other medications, including oral contraceptives. Don't use vitex if you're taking oral birth control pills, because vitex can cause them to become ineffective.

Vitex may not be safe to take if you have certain other conditions, such as Parkinson's Disease and cancers that are hormone sensitive, such as breast cancer and uterine cancer.

Again, talk with your healthcare provider for guidance before taking vitex.

Learn more:

• Ovulation calculator & calendar
• Early signs of pregnancy
• Home pregnancy tests
• When to see a fertility doctor