Women living closely together like in hostels tend to have the onset of their cycle closer with time. - Menstrual synchrony, a controversial hypothesis  (Source: www.abiyamo.com)

Seeing Menstrual Blood could cure a man love of sickness or even infatuation- Hypatia, a female Philosophers and Mathematicians in Egypt . (Source: www.abiyamo.com)

Contact with a menstruating women would “turn new wine sour, dry seeds, make fruit fall, and rust Bronze and iron- Pliny the Elder in Natural history (Source: The rhetoric of modern american menstrual taboo)

Women could not be educated since menstruation made women unable to understand intellectual matter. (Source: The rhetoric of modern american menstrual taboo)

If a person does not give away a maiden when she has reached her twelfth year, his Pitrs (ancestors) will have to drink every month her menstrual discharge. The parents and also the eldest brother go to hell on seeing an unmarried girl becoming Rajasvala (i.e. one who has had the experience of menstruation). The brahmanical justification for child marriage as well as enforced Motherhood is symbolically constituted in a threat to the ‘pitrs’. (Source: Parasara Smriti)

During her period she shall not apply collyrium to her eyes, nor anoint her body, nor bathe in water, she shall sleep on the ground, she shall not sleep in the day time, nor touch the fire, nor make a rope, nor clean her teeth, nor eat meat, nor look at the planets, nor drink out of a large vessel, or out of joined hands, or out of a copper vessel (Source: The Mythic Origins of the Menstrual Taboo in the Rig Veda.)

The Mae Enga people of Papua New Guinea believe that contact with menstrual blood or a menstruating woman will “sicken a man and cause persistent vomiting.” It will also “kill his blood so that it turns black, dull his wits, and lead to a slow death. (Source: The Curse: A Cultural History of Menstruation. Champaign, IL: University of Illinois Press)

In many parts of south India, a girl’s first menstruation was until recently celebrated publicly. After emerging from seclusion the young woman was bathed, dressed in bridal finery and garlanded with flowers. In tantric rituals, which probably have their origin in tribal and folk cultures, menstrual blood was one of the offerings made to the goddess. (Source: The Mythic Origins of the Menstrual Taboo in the Rig Veda.)

In rural Nepal, menstruating women are isolated in menstruation huts. The system of keeping girls and women apart is known as 'chhaupadi' ('padi' means 'woman'). (Source: article.wn.com)

Pliny describes in his Natural History that the “horrible” smell of menstrual blood drives dogs mad and even ants will throw away grains of corn that have been touched by it. (Source: The Curse: A Cultural History of Menstruation. Champaign, IL: University of Illinois Press.)

In a religion , she (menstruating woman) is “exempted” from rituals such as daily prayers and fasting, although she is not given the option of performing these rituals, even if she wants to.