Japanese women, as I understand it, favor pads to tampons by a wide margin. I think that's the case in most of Asia and the Spanish-speaking world.
Tampons allow women to completely or almost completely conceal their period, eluding that control.
Menstruation is also an indication that a woman is not pregnant. Remember, there are many people today who believe in the Evil Eye , a topic as interesting as menstruation. Menstruation has and certainly had a similar importance in many societies. Note the English in the ad, probably simple so that most school girls could read it. Most of the prestigious scholarly publications of the world are in English, making it advantageous for scientists and academics to learn it.