This word is acceptable for play in the US & UK dictionaries that are being used in the following games:

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v. Present participle of menstruate.

adj. discharging menstrual fluid; -- of women during their menstrual period.

"This study concluded that increased ferrous sulfate supplementation may be necessary to prevent iron depletion in populations at increased risk of developing iron deficiency anemia after RYGB surgery, such as menstruating women and patients with peptic ulcer disease."

unwell   

menstruate