Inversion Confusion.

Is it safe to go upside down when you're having your period?

By Timothy McCall, M.D.

Most yoga students are accustomed to hearing their teachers ask whether anyone is menstruating before leading the class into inversions. In many styles of yoga, such as Iyengar, doing inversions during your period is considered strictly verboten. Yet not all teachers consider menstruation an absolute contraindication to going upside down. 

From a yogic perspective, the reason for not inverting during menstruation has to do with apana, the hypothesized downward pranic force that is said to help facilitate things such as bowel function, urination, and menstrual flow. The concern is that reversing this normal energetic movement could interfere with the period, leading to a cessation of flow and possibly heavier bleeding later on. 

It may be wise to avoid inversions while menstruating. But from a medical standpoint, the belief is based mostly on speculation. Women are often warned that if they invert during their period, "retrograde menstruation" could occur. That is, blood could flow in the opposite direction and lead to endometriosis, a painful condition in which small clusters of uterine cells grow in the abdominal cavity. One study, however, found that retrograde menstruation naturally occurs in 90 percent of women, most of whom never develop endometriosis. So we do not know for sure if inversions increase retrograde flow or whether the backward flow increases the risk of endometriosis...

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Article by Timothy McCall from Yoga Journal.