The short answer: some essential oils are generally considered low-risk when properly diluted and used for aromatherapy or on the skin, but the evidence in pregnancy is limited, and a few oils are best avoided. Major bodies like the NHS and AAD note that essential oils are not well-studied in pregnancy, so caution is advised. This overview reflects what those authorities and dermatology guidance suggest, and it is not a substitute for your own provider's advice.
Essential oils are concentrated plant extracts, often used in aromatherapy (inhaled through a diffuser) or diluted into a carrier oil for skincare and massage. They are potent: a small amount contains a large dose of active plant compounds. The FDA regulates them as cosmetics or, in some cases, drugs, and does not formally review most for safety in pregnancy, so product quality and concentration vary widely between brands.
There is little high-quality research on essential oils in pregnancy, which is the main reason authorities urge care rather than a clear yes or no. The NHS advises pregnant people to be cautious with aromatherapy and to check with a midwife or a qualified aromatherapist, and the AAD notes many skincare actives are under-studied in pregnancy. Some oils are traditionally flagged to avoid, particularly in the first trimester, and undiluted oils can also irritate or sensitize the skin, which is more reactive during pregnancy.
Never swallow essential oils, and keep undiluted oils off your skin. Always dilute in a carrier oil, patch-test first, and use a diffuser in a ventilated room for short periods. Oils commonly named as ones to avoid or limit include clary sage, rosemary, and jasmine, especially early in pregnancy, though lists vary. When in doubt, unscented moisturizers, gentle fragrance-free skincare, and simply opening a window are low-risk alternatives, and a midwife or provider can advise on your specific situation.