Denise and her blog


Dr Denise Tiran HonDUniv FRCM, is an international authority on midwifery complementary therapies.

Watch our video and read Denise's blog for all the latest on complementary therapies and maternity care.


Find us on Facebook

Connect on LinkedIn

Hyperpolarisation

Published : 12/04/2021

Did you know that using too much clary sage aromatherapy oil to aid labour contractions can have the opposite and actually stop labour? Here, Denise discusses the growing incidence of hyperpolarisation arising from misuse of clary sage oil in labour. 

Clary sage is one of the most misused aromatherapy oils for labour. There is no doubt that it can aid the onset of labour when a woman is overdue. It may also help to accelerate the latent phase, encouraging contractions to become well established. However, both parents and professionals are over-using clary sage to the extent that I now receive reports on a regular basis of situations where labour has slowed down or even stopped despite the use of clary sage. Clary sage oil should be considered to be aromatherapy’s  equivalent of oxytocin and should only be used when there is a justification to use it to aid contractions; it is, of course, completely contraindicated until term pregnancy (37 weeks).

Prolonged use, excessive doses or continual environmental diffusion of clary sage oil can, in the first instance, cause excessively strong uterine contractions, possibly leading to fetal distress. However, continuing to use clary sage oil, administered either by inhalation or via the skin, may eventually cause a situation in which contractions slow down and eventually stop. This is a condition called hyperpolarisation, an effect that can occur with any pharmacological agent, including drugs, herbal remedies and aromatherapy essential oils. When a drug / oil is commenced, it triggers an action potential of the neurons in the relevant organ to make the body receptive to the substance  (this process is called depolarisation). In the case of clary sage oil, it stimulates an action potential to encourage the uterine muscles to contract. Eventually, a stage of optimum effect is reached, after which the oil becomes less effective (repolarisation). Ultimately, a state of hyperpolarisation is reached, in which the clary sage oil will start to have the opposite effect, namely relaxing the uterine muscles and interfering with the progress of physiological labour.

To prevent clary sage oil causing hyperpolarisation and leading to reduced or no contractions, midwives should:

  • Use clary sage in doses of no more than 3% to aid onset of labour
  • Avoid using clary sage once contractions have become well established
  • Avoid diffusion of clary sage (and other oils) in labour to prevent over-saturation of the atmosphere
  • Never use clary sage for the duration of a labour
  • Only use clary sage, in a 2% dose, to encourage labour that has slowed down if all other causes have been excluded (hypoglycaemia, full bladder, ketosis, obstructed labour, pain etc)
  • Be alert to the possibility that clary sage, if over-used, can have the opposite to the desired effect on contractions
  • Never use clary sage oil with drugs intended to facilitate labour



Previous articles

Hyperpolarisation

The Future of Midwives

Aromas Are Chemicals 

Informed Consent

The Debate on Cascade Training of Complementary Therapies

Denise's Latest Book

Thought For The Day...Clinical Hypnosis

A Few Words On Reflexology

Thought For The Day

How Times Change