It has been used for thousands of years as a way to reduce anxiety and stress while keeping fit.
But more recently expectant mothers have found yoga can help during pregnancy, although any evidence of its benefits have been anecdotal... until now.
Scientists at Newcastle University have studied the effects yoga can have on pregnant women and say it can make a real difference for both mother and baby.
Caireen Hart teaches pregnancy yoga in Gosforth in Newcastle. She says it is an important time for the mother to connect with her baby.
"It's an opportunity to have that time out for herself, to breath, to relax. That is an important part, the breathing, it helps the mother if she can control her thoughts, control her emotions, and that will help her to calm her whole body down and hopefully help to have a more happy birth experience."
Sarah Hunter is a regular at Caireen's yoga class. Her baby is due in July. She says the techniques she has learned have helped.
"I feel a lot calmer in anticipation of the labor that's coming. But, with the breathing techniques that we have been learning, I have already be able to put into good use to help me relax.
"The stretches that we do help me focus on the different symptoms and ailments that you get when you are pregnant such as indigestion or leg cramps.
"I seem to cope a little bit better a now that I have been doing the yoga."
Researchers at Newcastle University have published a paper looking at the effects of yoga on pregnant women, and found that it can reduce the risk of them developing anxiety and depression.
Stress during pregnancy has been linked to premature birth, low birth weight and increased developmental and behavioural problems in the child as a toddler and adolescent.
A high level of anxiety during pregnancy is linked with postnatal depression which in turn is associated with increased risk of developing depression later in life.
While it has long been assumed by medical professionals that yoga can help reduce stress levels in mothers, it had never been tested in a research setting.
But the paper, published with academics from Manchester University, shows that women who attended a yoga class a week for eight weeks had decreased anxiety compared to those who received normal antenatal treatment.
Dr James Newham at Newcastle University's Institute of Health & Society carried out the research. He said 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.”