Scientists have proved what Hollywood actresses such as Gwyneth Paltrow and hippy mothers have long known – yoga is good for pregnant women.

Researchers have studied the effects of yoga and found it can reduce the risk of anxiety and depression in mums-to-be.

A mother’s stress during pregnancy is recognised as being bad for the baby, and has been linked with premature birth, low birth weight and developmental problems in young children and even teenagers. Anxiety has also been linked with post-natal depression.

The results of new research led one expert to suggest yoga should be provided in national health care services as a cheap way of preventing serious complications later.

Yoga has been espoused by experts and celebrities as a way of de-stressing, and actresses such as Gwyneth Paltrow, Drew Barrymore, Jessica Alba and Sienna Miller are all said to have used the ancient techniques while pregnant.

And while medical professionals have long recommended yoga as a way of tackling stress, scientists have now tested the theory in a research setting.

In a paper published in the journal Depression and Anxiety, academics from Newcastle and Manchester Universities show that women who attended a yoga class every week for eight weeks experienced less anxiety compared to those who received normal antenatal treatment.

Dr James Newham, a research associate at Newcastle University’s Institute of Health and Society who carried out the work while at Manchester, says “It is surprising this has never been looked at before. We have long believed that it works but no research had been done to back up the theory. We have now gone some way to prove that it can help.

“It was not a small effect either. This has the potential to really help mothers who are feeling anxious about their pregnancy.”

Professor John Aplin, one of the senior investigators in Manchester and himself a yoga teacher, says the practice can be altered for pregnant women.

“Yoga incorporates relaxation and breathing techniques with postures that can be adapted for pregnant women,” he says. “Many women opt to practise yoga during their pregnancy but this is the first worldwide report on the effects of both single and multiple sessions of antenatal yoga on mood.

“The results confirm what many who take part in yoga have suspected for a long time.

“There is also evidence yoga can reduce the need for pain relief during birth and the likelihood for delivery by emergency caesarean section.”