A warning has been issued to pregnant women to avoid using a popular brand of bath soap because it contains ingredients that could trigger early labour.

Hayley Wright claims Radox muscle soak contains an essential oil called clary sage, which is believed to increase childbirth hormone oxytocin in the body, reports The Sun.

However the products makers, Unilever, insist the bath soak is safe for use and is “thoroughly assessed to ensure they meet our high quality and safety standards” before being sold.

Oxytocin is a hormone produced naturally by the brain that plays a role in pain relief, childbirth and breastfeeding.

It is the hormone that helps trigger labour and speeds up contractions.

But there is no scientific evidence that clary sage stimulates oxytocin and therefore induces labour.

Hayley posted the warning on her Facebook page, saying: “Clary Sage is an excellent pain killer but it should never be used during pregnancy especially during the first and second trimesters as it actually has the power to induce labour.

“There is not one warning label on this bottle that says ‘do not use during pregnancy’.

“I am going to report this to the company but in the mean time I’d appreciate people passing on this message to any pregnant ladies out there as this could cause some serious problems during pregnancy.”

Hayley added that she was not claiming the muscle soak alone would trigger early labour, just that it was something pregnant women should be aware of.

Her post has been shared over 85,000 times.

A spokeswoman for Radox said: “Our Radox Muscle Soak is completely safe to use and the very low quantity of clary sage present in the product does not lead to any adverse effects.

“All our products are thoroughly assessed to ensure they meet our high quality and safety standards as well as British and international regulatory standards.”

Have you ever been warned about clary sage during pregnancy?

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