A menstrual taboo is any social taboo concerned with menstruation. In some societies it involves menstruation being perceived as unclean or embarrassing, inhibiting even the mention of menstruation whether in public (in the media and advertising) or in private (among friends, in the household, or with men). Many traditional religions consider menstruation ritually unclean, although anthropologists of religion point out that the concepts 'sacred' and 'unclean' may be intimately connected. Where women's blood is considered sacred, the belief is that it should be ritually set apart. According to this logic, it is when sacred blood comes into contact with profane things that it becomes experienced as ritually dangerous or 'unclean'.
Different cultures view menstruation in different ways. Studies in the early 1980s showed that nearly all girls in the United States believed that girls should not talk about menstruation with boys, while more than one-third of girls did not believe it appropriate to discuss menstruation with their father. The basis of many conduct norms and communication about menstruation in western industrial societies is the belief that menstruation should remain hidden. By contrast, in many hunter-gatherer societies, particularly in Africa, menstrual observances are viewed in a positive light, without any connotation of uncleanness.
According to the anthropologists Buckley and Gottlieb, cross-cultural study shows that, while taboos about menstruation are nearly universal, and while many of these involve notions of uncleanliness, numerous menstrual traditions "bespeak quite different, even opposite, purposes and meanings." In some traditional societies, menstrual rituals are experienced by women as protective and empowering, offering women a space set apart from the male gaze and from unwanted sexual or domestic pressures and demands. An instructive example is provided by the anthropologist Wynne Maggi, who describes the communal bashali (large menstrual house) of women in the Kalasha Valley (northwestern Pakistan) as their 'most holy place', respected by men and serving as women's all-female organizing centre for establishing and maintaining gender solidarity and power. According to one body of cultural evolutionary scholarship, the idea that menstrual blood marks the body as periodically sacred was initially established by female coalitions in their own interests, although later, with the rise of cattle-ownership and patriarchal power, these same beliefs and taboos were harnessed by religious patriarchs to intensify women's oppression.
Bahá'u'lláh, the founder of the Bahá'í Faith, in the Kitáb-i-Aqdas abolished all forms of ritual impurity of people and things and stressed the importance of cleanliness and spiritual purity. Menstruating women are encouraged to pray and are not required to fast; they have the (voluntary) alternative of reciting a verse instead.
Some church fathers defended the exclusion of women from ministry based on a notion of uncleanness. Others held that purity laws should be discarded as part of the Old Covenant. In spite of the restrictions in Leviticus, Jesus allowed himself to be touched by a hemorrhaging woman and cured her (Mark 5:25-34).
In the Hindu faith, menstruating women are traditionally considered ritually impure and given rules to follow. During menstruation, women are not allowed to “enter the kitchen and temples, sleep in the day-time, bathe, wear flowers, have sex, touch other males or females.” Women themselves are seen as impure and polluted, and are often isolated as untouchables, unable to return to their family, for the length of their period.
The Qur'an only explicitly prohibits a menstruating woman from sexual intercourse. If a man is engaged in sexual intercourse with his wife and discovers that her period has started, he must immediately withdraw. However, fondling and embracing is permissible.
Authentic hadiths state that Islam exempts a menstruating woman from praying salah or completing the obligatory fasts during Ramadan, so as not to overburden her. Scholars argue that menstruating women are in a state in which they are unable to maintain wudhu, and are therefore prohibited from touching the Arabic version of the Qur'an, while recitation of its verses by memory or by sight is permitted. Similarly, other biological and involuntary functions such as vomiting, bleeding, sexual intercourse, and going to the bathroom invalidate one's wudhu. Reported interactions between Muhammad and his wife A'isha indicate that menstruation is seen as a natural part of a woman, and restrictions from fasting or praying are seen as a favor or mercy from God at a time where a woman already feels physically depleted. Although a woman may be unable to maintain her wudhu, she is only physically impure, and not spiritually. On authority of Urwah:
"A person asked me, 'Can a woman in menses serve me? And can a Junub woman come close to me?' I replied, 'All this is easy for me. All of them can serve me, and there is no harm for any other person to do the same. 'Aisha told me that she used to comb the hair of Allah's Apostle while she was in her menses, and he was in Itikaf (in the mosque). He would bring his head near her in her room and she would comb his hair, while she used to be in her menses.'"
Menstruating women are also prohibited from engaging in tawaf during Hajj. When A'isha wept to Muhammad when she was not able to perform tawaf on her menses, Muhammad responded, "This is a thing which Allah has ordained for the daughters of Adam. So do what all the pilgrims do with the exception of the Tawaf (Circumambulation) round the Ka'ba." 
In the Torah (Leviticus 15:19-30), a menstruating female is considered ritually unclean - "anyone who touches her will be unclean until evening" (New International Version). Touching a menstruating female, touching an object she had sat on or lain on, or having intercourse with her also makes a person ritually unclean. The extent to which these rules are observed in modern Judaism varies depending on the degree of conservatism/orthodoxy.
In Sikhism, woman is given equal status to man and is regarded as pure as man is. The Sikh gurus teach that one cannot be pure by washing his body but purity of mind is the real pureness. They are not called pure, who sit down after merely washing their bodies. Guru Nānak, the founder of Sikhism, condemned the practice of treating women as impure while menstruating.
In Sikhism, the menstrual cycle is not considered a pollutant. Certainly, it can have a physical and physiological effect on the woman. Nonetheless, this is not considered a hindrance to her wanting to pray or accomplish her religious duties fully. The Guru makes it very clear that the menstrual cycle is a God-given process. The blood of a woman is required for the creation of any human being. The requirement of the mother's blood is fundamental for life. Thus, the menstrual cycle is certainly an essential and God-given biological process. In other faiths blood is considered a pollutant. However, the Guru rejects such ideas. Those who are impure from within are the truly impure ones.
Meditating on God's name is of importance. Whether one's clothes are blood-stained or not (including clothes stained from menstrual blood) is not of spiritual importance. Thus, there are no restrictions placed on a woman during her menstruation. She is free to visit a gurdwara, take part in prayers and do Seva. In The Feminine Principle in the Sikh: Vision of the Transcendent, Nikky Guninder Kaur-Singh writes: "The denigration of the female body 'expressed in many cultural and religious taboos surrounding menstruation and childbirth' is absent in the Sikh worldview. ...Guru Nanak openly chides those who attribute pollution to women because of menstruation."
In some portions of South Asia, there is a menstrual taboo, with it frequently being considered impure. Restrictions on movement, behaviour and eating are frequently placed. For example, in some parts of western Nepal, the custom of chhaupadi requires menstruating girls and women to sleep in a hut some distance from the family home; this practise was banned by the Nepalese Supreme Court in 2005 but still continues. Two-thirds of girls in Sri Lanka were unaware of menstruation before reaching puberty. In addition, more than one-third of girls across South Asia do not go to school during menstruation.
A survey conducted in 1981 showed that a substantial majority of U.S. adults and adolescents believed that it is socially unacceptable to discuss menstruation, especially in mixed company. Many believed that it is unacceptable to discuss menstruation even within the family.
One common way that sanitary-product advertising avoids depicting menstruation is by pouring a blue, rather than red, liquid on the sanitary product to demonstrate its absorptivity. Further evidence of the taboo is the creation of a variety of euphemisms for menstruation, including "Aunt Flo", "on the rag", "my friend", or even "the curse".
In 2010, the "Always" tampon brand created the first feminine hygiene ad to ever feature a tiny red spot, representing blood. The ad was created by an intern who was working at Always' advertising agency, Leo Burnett. Originally the ad was created for the intern's personal portfolio, but then it caught the attention of the chief creative officer at Leo Burnett, and was subsequently published as an actual ad. There was some controversy when the ad was first released. In June 2016 the presence of red blood in a UK Bodyform commercial was greeted with approval in social media for its attempt to challenge the stereotypical menstruation ad, by showing women who struggle despite bleeding from cuts, blows and bruises they receive while playing various sports.
Movies and television also reflect the taboo nature of menstruation. Typically menstruation as a topic is avoided, except for scenes involving menarche or the first period. For example, as Elizabeth Arveda Kissling explains in her article, "On the Rag on Screen: Menarche in Film and Television", the early 1991 movie My Girl contains a scene where the main character, Vada, experiences her first period. The explanation given to her by a female role model of what is happening to her is done off-camera and the subject is never mentioned again, save when Vada pushes Thomas across the porch telling him, "Don't come back for five to seven days."
In the movie Carrie, the title character has her first period in the school gym shower, and the other girls tease her by throwing tampons and sanitary pads at her. The gym teacher tries to calm Carrie down, and eventually must explain the concept of menstruation to Carrie (because Carrie's mother had never done so). When Carrie returns home, her fanatically religious mother yells at her and throws her into a closet because menstruation is apparently a sign of sin. Later in the movie, her classmates mock her menarche again by pouring pig's blood on her at the prom.
In Only Yesterday, one of the girls is found to be going through menstruation and is later teased about it, especially when a group of boys tell the others not to touch a ball she had touched by saying, "You'll catch her period".
In the 2007 movie Superbad, Seth discovers menstrual blood on his jeans after dancing with a woman. He reacts with disgust, as do other men in the scene.
With the recent FDA approval of menstrual suppression medications, researchers have begun to shift their focus to the attitudes of American women toward their periods. One study in particular found that 59% of the women they surveyed reported an interest in not menstruating every month. Of these, 1/3 said they were interested in not menstruating at all anymore.
Menstrual activism (otherwise known as radical menstruation, menstrual anarchy, or menarchy) is a movement that addresses menstrual taboos. Overcoming this taboo is a point of contention amongst feminists. The primary argument behind this movement is that if menstruation is normal, there is no reason why the topic should be avoided: "After a while it becomes psychologically disorienting for women to look out at a world where their reality doesn't exist."
Menstruation can be conceptualized as a stigmatized condition that both reflects and reinforces women’s perceived lower status in relation to men. Feminist scholars extend this theory to explain negative attitudes towards women's bodily functions. Such stigmatization occurs when menstrual blood is viewed as one of the "abominations" of the body and reflects a gendered identity among women, which leads to consequences for women's psychological and sexual well-being.
Feminists such as Chella Quint have spoken against the use of shaming in advertising for feminine hygiene products. She created a zine, Adventures in Menstruating, to "help alter the visibility of menstruation, so that it's at least normal to talk about it. Because, right now, it's not". Other menstrual activists include Rachel Kauder Nalebuff, who published My Little Red Book; filmmaker and academic Giovanna Chesler, who created the documentary Period: The End of Menstruation; and artist Ingrid Berthon-Moine, who exhibited a video and series of photographs at the Venice Biennale.
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- Only they are pure, O Nanak, within whose minds the Lord abides. ||2|| (Siri Guru Granth Sahib Ji, Ang 472)
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