Peppermint Oil in Pregnancy and Nursing: What Is Published

No authority we could read says a bottle of peppermint essential oil is cleared for use in pregnancy, and none says it is forbidden. What they publish is narrower: a pharmacy-medicine page that expects no problems from capsules, a teratology service that advises against frequent skin use, and a government research centre that says little is known about amounts taken as a medicine. This article lays those statements side by side, says what each one actually covers, and says who to ask.

Peppermint Essential Oil bottle

Peppermint Essential Oil

Our own Peppermint Essential Oil, in sizes from 0.5 oz to bulk.

From $10.99

Shop Now →

Start with the route, because the sources do

"Peppermint" in a pregnancy source can mean four different things: tea, flavouring in food, an enteric-coated capsule taken for irritable bowel syndrome, or oil applied to skin. The statements below are not interchangeable. Our oils are sold neat, and our own safety copy says never to take them internally, so the capsule and tea statements describe products we do not sell. They are included because they are the statements people quote, and because comparing them shows how thin the evidence is.

Source and dateMaterial and routeWhat it says
NCCIH (NIH), updated May 2025Oral peppermintOral peppermint "in amounts commonly found in food is likely safe during pregnancy or while breastfeeding"; "little is known" about medicinal amounts.
NHS, peppermint oil medicine pagesCapsules for IBS"Although there is not much information on the use of peppermint oil in pregnancy, it is not expected to cause any problems." Breastfeeding: if your baby is healthy you can take it if you need to.
MotherToBaby, 10 November 2021Tea, and oil on skin"High levels of peppermint exposure during pregnancy can be a risk"; frequent peppermint oil on the skin or lots of peppermint tea "is not advised during pregnancy."

These three do not contradict each other as much as they first appear to. The NHS page is about a medicine with a set dose, taken after a clinician has decided it is warranted. MotherToBaby is talking about frequent, repeated exposure. NCCIH separates food amounts from amounts taken as a medicine. The common thread is that nobody quotes a dose below which skin or aroma use has been shown to be without effect in pregnancy, and nobody quotes a dose above which it has been shown to cause harm.

The uterine-muscle sentence, and what it does not give you

MotherToBaby's wording is the most specific: peppermint "can relax the muscles of the uterus and increase the risk for miscarriage." The blog page gives no study, no concentration and no route behind that sentence, and it attaches it to "high levels." We could not find, in the sources we read, a measured exposure from skin application or room aroma that reaches those levels. That is a gap, not reassurance. The practical reading is the authors' own: the more often and the more concentrated, the more reason to ask first.

The one skin trial in pregnancy, as a regulator summarised it

The Cosmetic Ingredient Review panel's 2018 re-review of peppermint-derived ingredients (CIR, 2018) summarises a triple-blind Iranian trial of 96 pregnant women with pruritus gravidarum, 47 given a 0.5% peppermint oil solution in sesame oil and 49 given sesame oil alone, applied to the itchy area twice a day for two weeks. CIR reports no side effects in the 47 women using the oil. We have not read the original paper, only CIR's summary of it, and the trial studied itching, which is not something we make claims about.

The arithmetic is worth doing, because it shows how small the studied exposure was. The women used a 60 ml bottle at 0.5%, which is 0.3 ml of oil in the whole bottle, about 6 drops at the usual 20 drops per ml (our arithmetic; droppers vary). One trial, 47 treated women, one peppermint species (Mentha piperita), one concentration, two weeks. It does not tell you what happens at 2%, on a larger area, with a diffuser running all day, or with the cornmint (Mentha arvensis) oil we also sell. We are reporting it so you can see how far the evidence reaches. It is not a dilution recommendation for pregnancy, and we do not give one.

Breastfeeding: two different questions

The NHS statement above concerns capsules taken by the mother. It does not address oil on the mother's chest or neck, where an infant's face may rest. For that, the only direct statement we read is NCCIH's: "Peppermint oil should not be applied to the face of infants or young children." Our own distillation page says the same in its own words: do not apply it near the face of an infant or young child, where concentrated menthol can affect breathing. A breastfeeding parent who wears peppermint oil on skin the baby touches is in that territory, and the question belongs with a paediatrician or midwife. MotherToBaby's page does not discuss breastfeeding for peppermint specifically, and we could not retrieve the LactMed entry, so we make no statement about milk supply.

What we can say about our own oils

One number from the regulatory side is relevant to reading any dilution advice. CIR reports a recommended maximum dermal level of 5.4% for peppermint oil, attributed to Tisserand and Young's 2014 book (we read it second-hand, in CIR), calculated from 8% menthofuran and 3% pulegone in the oil. That is a figure for the general population, not for pregnancy, and it is above the 2% top of our own copy. We do not treat it as a target. For anyone, pregnant or not, our stated recommendation is the low end, 0.5% to 1%, for face and body, because menthol irritates and peppermint is potent.

Who to ask, and when not to wait

Ask your obstetrician, midwife or pharmacist before using any essential oil, including in a diffuser, and mention every medicine you take: NCCIH says to talk to your health care provider about herbal products if you take any medicine, and peppermint oil has been shown to raise blood levels of at least one drug in a small study. In that study of 12 volunteers, 600 mg of oral peppermint oil raised the exposure (AUC) of the blood-pressure drug felodipine to 140% of the water baseline (Dresser et al., 2002). That was an oral dose, not skin or aroma use, and it says nothing about pregnancy; it is one reason the "tell your clinician" advice exists.

After a swallow of any essential oil, the US poison centre line is 1-800-222-1222, free and open all day (poison.org). The NHS page on side effects says to call 999 for swelling of the lips, mouth, throat or tongue or difficulty breathing after peppermint oil, and to call a doctor or 111 for a widespread itchy rash.

For related reading, our safety basics and children posts cover patch testing and the infant-face rule, and the FAQ covers handling. For nausea, which is the usual reason pregnant readers search for peppermint, the evidence is covered in what aromatherapy trials measured; a clinician, not a bottle of oil, is who to ask about it.

If you are pregnant or nursing and want peppermint in a room or on skin, the decision is one for your obstetric clinician, not for a seller. Our oils are there if they say yes.

Peppermint Essential Oil bottle

Peppermint Essential Oil

Peppermint Essential Oil from our own shop, in sizes from 0.5 oz to bulk.

From $10.99

Shop Now →

Sources & Further Reading