Some husbands fast with their wives on Karva Chauth, out of love and to respect the fast the wife is keeping for their good health and long lives. That is a sweet way of following tradition while addressing its unevenness with respect to gender. If a man also has a headbath after wife's 4th day of period, it would be a nice way of the household getting back to a pure state together. A puzzled MIL wondering why both are having headbath on an unusual day in the peak of winter, would be an added bonus. Now, "headbath" has firmly ensconced itself in my vocabulary. The impurity of having "headbath" in my vocabulary.