Tansy is a very strong herb, please read through the following infomation carefully and thoroughly.
The herbalists who've I've read and interviewed generally agree that an infusion of tansy (tea) may be used safely but with caution, dosages and duration should not be exceeded. The chemicals the herb contains, its constitutes, can vary widely from plant to plant, and if you choose to work with this herb it should always be started with the lowest dosage and gradually work up to the appropriate dosage to test the herb's strength. If possible consult with an herbalist or midwife, especially when using herbs that are known to cause side effects. Always proceed with caution, and at first sign of toxicity, reduce or discontinue taking the herb.

The essential oil, as with any abortifacient herb, should never be taken internally, it is leathal in small amounts. Tansy's main constitute, thujone is toxic, and very concentrated in the oil. Thujone also has a potent action on the uterus, its a uterine stimulant. Again I want to stress, this is a strong herb and it has been known to cause side effects even when used in small amounts, causing temporary lumps in the breasts, can cause women who normally bleed heavily to hemorrhage. And those who've had epileptic seizures should not use this or any herb which contains the chemical thujone.

Susun Weed writes in her book The Child bearing Year one midwife reports that a Tansy tincture definitely induces abortion even when menstruation is several weeks overdue. She uses 10 drops of the tincture in a cup of warm water every 2 hours until bleeding begins. This means during the night too, setting the alarm at two hour intervals.³

One of Susun's students has used Tansy as a back up to her regular birth control method for years, claiming she's never been late yet. When necessary she drinks an infusion of the flowers and leaves for a week before her period is due.³

Michael Tierra writes: "I once clinically saw a woman who claimed to rely solely on tansy tea to induce pregnancy each month and used no other birth control. She said that around the time her period was do, she would drink one strong cup of tansy tea in the evening and her period would be there the next day. Sometimes it might require two cups but never more than that. I don't think even three or four cups of tansy tea is harmful and in fact it is a very useful acute herbal medicine herb for worms, fevers, colds, stopped menses, nausea and as a lotion for scabies. The woman using the tansy, used a handful of the dried aerial part of the herb or a handful and a half of the fresh aerial parts steeped in one or two cups of water. She'd said she would drink one cup in the evening and one in the morning to bring on menstruation each month. No more than that was needed."

If you choose to work with Tansy to terminate pregnancy, it is very important to follow up with a clinical abortion if it does not work. Tansy contains thujone, which is known to be mutagenic, meaning that it disrupts normal DNA and cell replication, causing birth defects. Not to follow up with a clinical abortion would be pretty irresponsible. Again, I want to stress, that before you attempt to use any herb to terminate pregnancy, it is extremely important to be committed to ending the pregnancy, even if it means going through with a clinical abortion.

Contradictions: women who normally menstruate heavily³, anyone with epelipsy, liver problems, kidney problems, phototoxic (meaning it can make skin extra sensitive to sunlight and may cause burning of the skin, or rash if skin is exposed to the sun)⁴.

Signs of toxicity specific to tansy:
Nausea, vomiting, inflamation of the stomach lining, dilated pupils, weakened and/or rapid pulse, convulsions, coma. ⁴

Dosing:
Tansy should be used with caution, and at first signs of toxicity herbs should be reduced or discontinued. Also I think it would be best to use tansy for no longer than 5 days, 7 max. Also, I think its probably a herb best used by itself.
The dried herb or tincture may be used. All parts of the plant are used.
The tincture is very difficult to find, unless it is home made, it is unlikely that it will be found on the shelves of any store. I have heard that it is available only to practitioners of herbal medicine. The bulk herb, for making tea can be found, although not all stores will carry it. I know that some places do carry it. I have also found the potted herb for sale at my local garden center, and now have it growing in a pot in my garden (it likes to spread if not contained)

To make a tea, use ¹/₂ to 1 teaspoon (tsp) of the dried herb per cup of water 3-4 times a day. For up to 7 days.⁴
Tincture: ¹/₄ to ³/₄ tsp in a cup of warm water 3-4 times a day.⁴
Powder: 3-8 size #0 capsules 3-4 times per day⁴

The essential oil of this herb is known to be poisonous, and should NEVER be taken orally/internally, because it can kill you even in small doses. This herb, as any of these herbs, commands respect.

Tansy is some times used in conjunction with other herbs like Blue Cohosh and Pennyroyal. But again, my opinion, is that it is a herb that should be used as a simple (which means by itself)

Tansy should not be used in combination with Vitamin C, as they can counteract each other.

Note: Don't confuse Tansy (Tanacetum vulgare) with Tansy Ragwort (Senecio jacobace) which causes irreversible liver damage and has been known to kill cattle who ate it. This is why we use the scientific names, because each plant has its own. Common names mean different plants to different people, scientific names - difficult to remember and pronounce avoid this confusion, so write it down. If you are purchasing Tansy from a store, there should be no problem. When trying to identify plants in the wild is where you may run into problems. But it is good to know the scientific name and be able to recognize it when you see if even if you don't remember it off the top of your head.

To order your herbs online:

Online herb shops

If you or anyone you know has attempted herbal abortion, I am currently collecting data for a herbal abortion database, I have created a questionnaire to assist me in collecting data, and any and all herbal abortion or emergency contraceptive experiences are welcome, pregnancies confirmed with a pregnancy test are most useful, but as stated, all experiences are welcome, even if pregnancy was not confirmed or menstruation was simply late. I have posted some of the database findings on the website. You can read about other women's experiences in the Sharing our Wisdom section, all of these women have helped to add to our body of knowledge.

Fertility Awareness Section		Preventing and Ending Pregnancy