It reduces the number of oestrogen in your body
This is only the issue for women who have the issue with the menstrual cycle. When you drink hibiscus on a regular basis, it can slow down the process of oestrogen production.
So, if you already have problems with this in your life, then consider staying away from karkade for a while. Besides, you should also remember that women taking birth control pills should stay away from the tea too, because of its specific properties.
Thus, if you have such problem, then opt for some other tea instead of this one and eliminate it from your daily diet at all.