Why shouldn’t we do inversions (viparita sthitti) during the period?
During menstruation if one does inversions the blood flow will be arrested. Those who tried to do out of enthusiasm or callousness will have noticed that the flow stops abruptly. This is certainly not good for health since it may lead to fibroids, cysts, endometriosis and cancer, damaging the system.
According to ayurveda, whatever has to be thrown out should be thrown out and not retained or held in. You cannot hold urine, faeces, phlegm, mucus etc, inside as they are substances that have to be thrown out. These are called as mala – the waste, which need to be excreted.
If they are retained within they invite all diseases. During menstruation one has to lessen physical exertion including walking, dancing or heavy house-hold work. The body demands rest and relaxation and one needs to provide that.
If this background, as far as the effects of inversions are concerned are known, one need not doubt about their omission during the periods. Still, due to obstinacy and rigidity, if one forces oneself to do one may have to pay heavily later if not immediately. The flow has to stop completely before one can resume the practice of inversion. The question is not of three days or four days. As soon as the flow stops, begin with the practise of inversions. Do not go suddenly for standing poses, back-bendings, balancings etc,. Remember that you have just delivered the unborn baby, since the menstruation is called as the funeral of the unborn baby.
Geeta S. Iyengar (Pune Feb 2003)