Vitex (Chasteberry), Fertility
and PCOS

Vitex agnus-castus (chaste tree berry) is a well-known herb that has been used for centuries in Europe for hormonal imbalances in women.

It may help women with PCOS who are lacking a normal menstrual cycle and thus don't ovulate or menstruate. A high percentage of these menstrual problems are related to insufficient progesterone during the luteal phase of the menstrual cycle. This condition is called a luteal phase defect or corpus luteum insufficiency. A corpus luteum insufficiency is defined as an abnormally low progesterone level 3 weeks after the onset of menstruation. Insufficient levels of progesterone may result in the formation of ovarian cysts.

In addition, some PCOS women have too much prolactin, which can inhibit fertility. Vitex may help with both of these problems

"I've spent thousands of dollars, been to five different gynecologists and had no results from their treatment for PCOS for the past ten years. It was one of your success stories that gave me the courage to try the alternative.

I'm happy to tell you that I took the vitex tablets and I am now 3 months pregnant. My husband and I are very happy. I now definitely believe that alternative medicine is the best way to go."

- Janet Beckford

Get High Quality Vitex from our PCOS Supplements Store

How does Vitex Work?

Chaste tree berry acts on the hypothalamus and pituitary glands inside your brain by increasing luteinizing hormone (LH) production and mildly inhibiting the release of follicle stimulating hormone (FSH). The result is a shift in the ratio of estrogen to progesterone, in favor of progesterone. The ability of chaste tree berry to raise progesterone levels in the body is an indirect effect, so the herb itself is not a hormone.

When you don't ovulate to start the second half of your monthly cycle, your body does not produce enough progesterone. The resulting progesterone deficiency contributes to symptoms of PCOS. It also contributes to a hormone imbalance called "estrogen dominance". Women with polycystic ovary syndrome frequently have estrogen dominance combined with a progesterone insufficiency. This is part of the hormonal imbalance typically associated with this disorder.

If you were to take oral progesterone or apply progesterone cream to your skin, and a normal cycle occurs, then you can suspect that you have a problem producing enough progesterone.

Chaste tree berry helps your body to solve this problem.

A progesterone-induced menses indicates an intact reproductive system that just isn't going through its cycle. It suggests that the body is producing enough FSH to stimulate the ovaries, and that the ovaries are able develop follicles. It also indicates that production of estrogen by the follicles is sufficient to cause the lining of the uterus (endometrium) to grow and that the sloughed endometrium is able to pass through the cervical opening and the vagina.

Therefore it's possible that the problem is a dysfunction in your hypothalamus or pituitary glands in your brain. The ability of chaste tree to influence the hypothalamus or pituitary then makes this herb a good possibility for treating infertility associated with lack of a normal monthly cycle.

Also, high levels of the hormone prolactin are commonly found with corpus luteum insufficiency. Vitex is useful for reducing high prolactin levels. It inhibits prolactin release by the pituitary gland, especially when you are under stress.

Is Vitex a Hormone?

Vitex is not a hormone, nor does it contain hormones. It is a gentle and slow-acting herbal extract as opposed to a hormone prescription that can be expected to have a forceful and immediate impact on your glands and organs.

It does not have the side effects that synthetic hormones have.

What's the Medical Evidence for Vitex Agnus Castus?

There's not a huge body of research about the chaste tree berry in relation to PCOS. However, there is enough evidence to suggest that it could be useful for issues associated with polycystic ovary syndrome such as infertility, acne, hyperprolactemia, female hair loss, and chronic inflammation.


In one study, a chasteberry preparation was used in a study of 3,162 women to assess the effectiveness of vitex for corpus luteum insufficiency. 77.4% had menstrual cycle disturbances of various types and the others suffered from a range of gynecological problems which included symptoms of corpus luteum insufficiency. The average length of treatment was 5 months.

One-third of the women reported the treatment to be completely effective. Fifty-five percent reported significant improvement , and only 7% reported no improvement. Their doctors reported very good results in 68% of cases, adequate in 22%, and no change in 7%. (1)

In another research study, 20 women with secondary amenorrhea took the extract for 6 months. Lab testing was done to measure progesterone, FSH, and LH, and pap smears were done at the beginning of the study, at 3 months, and at 6 months. At the end of the study, the researchers were able to evaluate 15 of the women. Ten out of the 15 women had a return of their menstrual cycles. Testing showed that values for progesterone and LH increased, and FSH values either did not change or decreased slightly.(2)

In a third study, 18 women with abnormally low progesterone levels were given chaste tree berry extract daily. After 3 months of treatment, 13 showed increases in progesterone and 2 became pregnant.(3)


In one research study, fifty two women with luteal phase defects due to latent hyperprolactinemia (high prolactin levels) were given either vitex or a placebo. Prolactin levels were normalized after three months in the treatment group and deficits in luteal progesterone production were eliminated. Two of the women became pregnant.(4)

In another study, 13 women with high prolactin levels and irregular cycles were given a vitex compound. Their prolactin levels fell, and a normal menstrual cycles returned to all of the women.(5)


In this study, a chasteberry preparation was used in women with menstrual cycle abnormalities. Acne was either eliminated or improved during treatment.(6)

In another study, 117 women with four different types of acne were treated with a chasteberry preparation for 1-2 years. Improvement was seen after 6 weeks and by 3 months, about 70% were free of acne. Some treatment relapses were observed after 3-6 weeks.(7)

Chronic Inflammation and Hair Loss

The extract also appears, according to some medical studies, to reduce chronic inflammation. Chronic inflammation is a major contributor to all chronic diseases, including PCOS, diabetes and heart disease.

For example, chronic inflammation causes your ovaries to produce more male hormones. An excess of male hormones cause hair problems such as hirsutism and hair loss.

How Much Should You Take?

Don't expect immediate results if you take chaste tree berry extract. You may need to take it for 2-6 months before you can expect to notice any effect. Chasteberry can be taken daily for up to 18 continuous months, unless pregnancy occurs. Vitex can be taken once or twice a day.

It's not the same as taking progesterone. You don't take it, stop it, and then expect a withdrawal bleed a few days later as you would if you were taking progesterone or synthetic progestins.

Vitex agnus castus is exceptionally safe. In one study, chaste tree berry was given up to 9 years with very few side effects. But it's advisable to not take it if you are pregnant.

Every person is unique, so the amount and form of vitex you need won't be the same as for the next person.

We recommend you seek guidance from a licensed naturopathic doctor. They have extensive knowledge of herbs and botanical medicines.

If you don't consult with a qualified health professional, a general guideline for your daily dose could be:

  • 60 drops of vitex tincture, standardized to contain 0.6% agusides.
  • 175 mg. or more of standardized vitex extract, standardized to contain 0.6% agusides.

Please note: The quality of botanical supplements is unreliable. Don't buy any herbal or botanical product unless it has a "standardized" amount of the active component listed on the label. A "standardized" product has a consistent amount of active ingredients from one bottle to the next. If you buy a product that is not standardized, you have no clue as to what you are actually getting and are probably wasting your money.

Where Can You Get It?

You can obtain the highest quality vitex product from our PCOS Supplements Store.

Drug Interactions

Interactions with hormone replacement therapy (potential/theoretical). Animal studies and human data have reported that chasteberry constituents have hormonal activity that may alter the effects of these medications and possibly the dose needed for treatment. conjugated estrogens, estradiol, estrone, esterified estrogens, estropipate, ethinyl estradiol, progesterone, medroxyprogesterone, hydroxyprogesterone, norethindrone.

Interactions with oral contraceptives (potential/theoretical). Animal studies and human data have reported that chasteberry constituents have hormonal activity that may alter the effects of these medications and possibly the dose needed for treatment: norethindrone, ethynodiol diacetate, norgestrel, norgestimate, ethinyl estradiol, drospirenone, desogestrel, levonorgestrel .

Interactions with dopamine agonists (potential/theoretical). An in-vitro study reported that chasteberry constituents had dopaminergic activity that may alter the effects of these medications and possibly the dose needed for treatment: selegeline, amantadine, carbidopa, levadopa, pramipexole, ropinirole, bromocriptine, pergolide. If you are taking any of these medication, it's a good idea to consult with your physician before taking this compound.

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