(Date of issue: October 2014. Version: 2)
This factsheet has been written for members of the public by the UK Teratology Information Service (UKTIS). UKTIS is a not-for-profit organisation funded by Public Health England on behalf of UK Health Departments. UKTIS has been providing scientific information to health care providers since 1983 on the effects that medicines, recreational drugs and chemicals may have on the developing baby during pregnancy.
What are essential oils?
Essential oils are perfumed oils that contain very high concentrations of plant extracts. When used in an aromatherapy massage or in oil burners, a small amount of the concentrated essential oil is usually diluted with another ‘carrier’ oil. Some everyday toiletries, cosmetics, and foods and drinks also contain very small amounts of essential oils. Some essential oils are poisonous if used in their pure form (undiluted).
Is it safe to use products containing essential oils during pregnancy?
The levels of essential oils found in commercially available foods and drinks are generally low and would not usually be expected to pose a risk to your unborn baby. However, it is advisable to always read any product information.
The level of essential oils found in everyday perfumes, cosmetics, skin care products and toiletries is generally low and is therefore very unlikely to pose a risk to your unborn baby. However, it is always important to check the product information to see if avoidance in pregnancy is advised. It is also important to avoid products from unknown suppliers, e.g. unbranded products sold on the internet as these may not go through safety and quality control checks, and may also contain other substances that could be potentially harmful to a baby in the womb.
Although no large scientific studies have been carried out to assess whether the use of essential oils for pregnancy massage is ‘safe’, it appears that many pregnant women undergo aromatherapy massage without problems. As a precaution, some women (and massage therapists) prefer to avoid aromatherapy massage during the first trimester while the baby’s body and internal organs are being formed. It is, however, recommended that certain specific essential oils are not used for massage at any stage of pregnancy (see below).
Essential oils are absorbed through the skin and can enter the bloodstream, with amounts increased if a large area is being massaged, or if the skin is broken. A number of essential oils are said to stimulate contractions of the womb and these should be avoided during pregnancy.
Historically certain essential oils were used (usually taken by mouth) to induce miscarriage, although it is now thought that in many cases where this resulted in loss of the baby, this was because of severe poisoning in the mother (sometimes even resulting in her death) rather than because the essential oil had specific effects on the pregnancy. Although it is unclear how this information relates to essential oils applied to the skin, use of certain oils for massage during pregnancy should be avoided. If you are unsure about which oils can be used in pregnancy, you should seek advice from a trained professional.
Some essential oils (e.g. eucalyptus, camphor, menthol and others) have decongestant properties and are commonly used to treat a blocked nose. Combinations of these oils are present in commercially available inhaled decongestants (e.g. Olbas Oil, Vicks VapoRub, Karvol). The manufacturers of these products recommend that pregnant women consult their doctor before use. Although there are no specific pregnancy safety studies of these products, one small study of around 170 pregnant women who had applied oil of camphor (an ingredient in Vicks VapoRub) to their skin in early pregnancy showed no link to an increased risk of birth defects in their babies.
Citronella oil is often applied directly to the skin as an insect repellent. Although generally only a small amount is applied for this purpose, and citronella oil is not known to be harmful when used in this way, there are no pregnancy safety studies on citronella oil so we cannot say for sure that it is safe for use in pregnancy. Please see the bumps leaflet on use of insect repellents in pregnancy if you require information on this subject.
Clove oil is a traditional remedy for toothache. There are no pregnancy safety studies on clove oil so we cannot say for sure that it is safe for use in pregnancy. There are, however, a small number of isolated reports of women using clove oil for toothache during pregnancy, the majority of whom delivered healthy babies.
Use of essential oils in labour
Essential oils (either inhaled or applied to the skin) are sometimes used by women during labour for pain relief, and/or because some are thought to stimulate contractions of the womb. No evidence of harm to either mother or baby was seen in a single study of 250 pregnant women using one of the following essential oils during labour: lavender, mandarin, Roman chamomile, frankincense, or clary sage.
Essential oil poisoning
Undiluted essential oils are highly toxic and should not be swallowed during pregnancy or at any other time. Undiluted essential oils should also not be applied to the skin as they can cause severe irritation and/or allergy. If you swallow an essential oil you should seek immediate medical advice.
Who can I talk to if I have questions?
If you are pregnant or planning a pregnancy and are in any doubt about using a product or medicine, speak to a trained professional or healthcare advisor such as your midwife.
Up to 1 out of every 5 pregnancies ends in a miscarriage, and 1 in 40 babies are born with a birth defect. These are referred to as the background population risks. They describe the chance of these events happening for any pregnancy before taking factors such as the mother’s health during pregnancy, her lifestyle, medicines she takes and the genetic make up of her and the baby’s father into account.
Medicines use in pregnancy
Most medicines used by the mother will cross the placenta and reach the baby. Sometimes this may have beneficial effects for the baby. There are, however, some medicines that can harm a baby’s normal development. How a medicine affects a baby may depend on the stage of pregnancy when the medicine is taken. If you are on regular medication you should discuss these effects with your doctor/health care team before becoming pregnant.
If a new medicine is suggested for you during pregnancy, please ensure the doctor or health care professional treating you is aware of your pregnancy.
When deciding whether or not to use a medicine in pregnancy you need to weigh up how the medicine might improve your and/or your unborn baby’s health against any possible problems that the drug may cause. Our bumps leaflets are written to provide you with a summary of what is known about use of a specific medicine in pregnancy so that you can decide together with your health care provider what is best for you and your baby.
Every pregnancy is unique. The decision to start, stop, continue or change a prescribed medicine before or during pregnancy should be made in consultation with your health care provider. It is very helpful if you can record all your medication taken in pregnancy in your hand held maternity records.