Ruth Gilmore was plenary speaker at the latest British Wheel of Yoga Congress. As a doctor and Yoga teacher she discussed various claims concerning the benefits of Yoga.
I was keen to have her views on inversions during a period.
She wrote back in details the following message:
Here are the views against inversions during a period, followed by my comments on each:
1. It MAY cause endometriosis by encouraging the menstrual flow to pass along the uterine (Fallopian) tubes into the abdominal cavity. If the degenerated womb lining contains any healthy cells they might survive within the abdominal cavity and bleed each month, causing the condition.
BUT [My comments – the cause of endometriosis is not clearly understood, there are two main THEORIES,
(a) that during embryonic life cells that should develop as womb lining (endometrium) spread into other areas of the body and develop there, responding every month to the same hormones that cause the womb lining to build up and then bleed. This theory can explain why endometrial tissue can be found in areas distant from the womb, such as the chest and even in the nose.
(b) That the menstrual flow can possibly contain some healthy cells that could pass via the uterine tubes into the abdomen and develop as areas of endometriosis. This theory explains away the finding of such tissue outside the abdominal cavity by saying that cells might get into the blood or lymph and travel that way.
In my view (a) might be possible. (b) is COMPLICATED by the fact that in very many women the flow (which pools in the womb cavity at night as most women know, because they experience a greater flow when they get up in the morning) does go along the tubes at least to some extent – this happens in far more women than those who have endometriosis. Normally if there were living cells in the flow (and I don’t know to what extent this is the case), the immune system would seek them out and destroy them. Thus retrograde flow can only be a cause of endometriosis if the woman has a specific immune deficiency that prevents such immune response, and inverting will make no difference to whether they develop it or not.]
2. EMBARASSMENT During inversions the flow will pool in the womb, and will run out when the woman becomes upright again. If the flow is heavy this could cause STAINING of the outer clothing or mat and be embarrassing. [I agree with this, and advise against prolonged inversions when the flow is heavy for this reason.]
3. TIREDNESS During a period many women are tired and would benefit more from a gentler practice without the work of sustained inversions [I agree with this but have come across women who actually like them at this time.]
4. MYSTICAL Considering it from the point of view of the energy body, at this time the net pranic flow is downward, so it seems inappropriate to turn upside down. [I accept this way of thinking, although it has NO SCIENTIFIC EVIDENCE in favour of it, being a mystical concept.]
So, all in all, in my view there is no medical or scientific reason not to invert if one wants to, and just as importantly, there is not reason why one should if one doesn’t want to!
I hope this is helpful. Let me know if you need more details.