So I've been asked in a couple of occasion, what are the oils considered UNSAFE to use during pregnancy. Here are some of the common essential oils to avoid and why. Do note that this list is not exhaustive and those in red fonts are best avoided during pregnancy. If in doubt, always consult a licensed medical professional for advise and always use essential oils with extreme precaution during pregnancy.
- Aniseed (Pimpinella anisum) - Promote menstruation and facilitate birth.
- Angelica (Angelica archangelica) - It is said to regulate menstrual flow and ease painful periods by relieving cramps in the uterus and encouraging the production of estrogen. May cause womb contractions.
- Basil (Ocimum basilicum) - It may inhibit blood clotting. A uterine stimulant; use only during labour.
- Black pepper (Piper nigrum) - Skin sensitisation.
- Camphor (Cinnamomum camphora) - Excessive use can break down the red blood cells.
- Cedarwood (Cedrus atlantica) - Emmenagogue, stimulates or increases menstrual flow.
- Cinnamon (Cinnamomum zeylanicum syn. C. verum) - Large amounts can lead to liver toxicity.
- Chamomile, Roman chamomile (Chamaemelum nobile syn. Anthemis nobilis) - May cause contractions, miscarriage or premature labour. May cause allergic reactions.
- Clary Sage (Salvia sclarea) - Strong womb-stimulant. May cause miscarriage or premature labour if used before 37 weeks of pregnancy. Large doses in labour may cause fetal distress from very strong contractions.
- Clove (Syzgium aromaticum syn. Eugenia caryophyllata) - May cause blood-clotting problems and liver complications. Dermal and mucous membrane irritant and sensitiser.
- Fennel (Foeniculum vulgare) - May cause contractions, miscarriage or premature labour, as well as allergic reactions. Promote menstruation and facilitate birth.
- Fir (Abies alba) - Skin sensitisation.
- Ginger (Zinger officinale) - Large amounts may cause blood thinning, so avoid if you have a history of miscarriage or have any vaginal bleeding during your pregnancy. Excessive amounts may cause abdominal discomfort, heartburn and itchiness. Don't have more than about three teaspoons of grated root ginger a day.
- Horseradish (Armoracia rusticana) - May cause miscarriage. Irritant effects on lining of the mouth, stomach, and intestines.
- Hyssop (Hyssopus officinalis) - Strong sensitiser and skin irritant.
- Jasmine (Jasminum officinale) - May cause contractions, miscarriage or premature labour in pregnancy, but may be used in labour.
- Juniper (Juniperus osteosperma syn. J. scopulorum) - May cause miscarriage. Emmenagogue, stimulates or increases menstrual flow.
- Marjoram (Origanum marjorana) - Emmenagogue, stimulates or increases menstrual flow.
- Mustard - Allyl isothicyanate, extremely toxic and irritating to skin and mucous membranes.
- Mugwart (Artemisia vulgaris) - May cause miscarriage, premature labour, abnormalities in your baby and allergic reactions.
- Myrrh (Commiphora myrrha)- May stimulate the womb, causing miscarriage or premature labour.
- Nutmeg (Myristica fragrans) - May cause miscarriage or premature labour.
- Oregano (Origanum vulgare) - Skin sensitisation
- Peppermint (Mentha piperita) - May cause heartburn, nausea, vomiting and allergic reactions, including skin irritation, when the oil is used on skin.
- Rosemary (Rosmarinus officinalis) - May cause contractions if consumed in large amounts. The essential oil increases blood pressure and may trigger seizures if you have epilepsy.
- Sage (Salvia officinalis) - May trigger bleeding and cause miscarriage.
- Tansy (Tanacetum vulgare) - May stimulate the womb, leading to miscarriage or premature labour. Long-term use may cause vomiting, fits, kidney and liver damage, breathing difficulties, irregular heartbeat, and loss of consciousness.
- Thyme (Thymus vulgaris) - Allergic reactions may occur with prolonged use.
- Wintergreen (Gaultheria procumbens) - Toxic, contains high amounts of Methyl salicylate and when taken internally can be fatal.
- Wormwood (Artemisia absinthium) - Contains camphor, thujone and sabinyl acetate. All three aren’t good for you during pregnancy. Apart from that it is also an abortifacient.
*Plant types in red to be avoided entirely during pregnancy.