The first time 19-year-old Zoha Qamar went to Friday prayers during her period, the mosque was packed. She had learned from a young age that menstruating women aren't supposed to pray, as dictated by Islamic law and custom.

Typically, they would shuffle to the back of the women's section when the call to prayer began, removing themselves from the area designated for prayer. But on this particularly day, Qamar said, the mosque was so full that even the back had to be occupied by praying women.

"There came a point when I had to leave the room because it was so crowded," Qamar told The Huffington Post. "The fact that there wasn’t even space for me to observe was heartbreaking and hard for me to digest as a 12-year-old.”

IvancoVlad During their periods, Muslim women aren't supposed to pray, have sex or fast for Ramadan.

Rules for menstruating women take on special significance during Ramadan, the Muslim holy month of fasting and prayer. Not just restricted from praying, women on their periods are also excused from fasting during the days of their menses.

The topic of menstruation and how it affects Muslim women's observance, especially during Ramadan, comes up in article after article online. But where it fits in the larger context of faith -- and the effect this has on Muslim women's identity -- is rarely investigated in depth. Call it a prohibition, a custom, or a welcome break from fasting -- there's more to the rule than meets the eye.

'Cleanliness is half the faith.'

Hygiene plays a prominent role in Islam year round, though certain rituals of purification may be tied to specific events like Ramadan. One collection of hadith, or sayings of the Prophet Muhammad, called Sahih Muslim, states that "cleanliness is half the faith." A long list of rules on cleanliness and purification are described in the Quran and hadith and covered at length by Islamic jurists. These rules range from how to wash after using the toilet to how a man must trim his beard.

There are also acts of purification observant Muslims do after sexual intercourse and during menstruation.

“These things constitute a type of transgression against a state of purity,” Muslim researcher Donna Auston told HuffPost. “Menstruation and how it’s handled exists within that context."

But the concept of "transgression" shouldn't be looked down upon, Auston said.

“Going to the bathroom, having sex, menstruating, bleeding, vomiting -- these are all basic biological functions that don’t have an assigned value as good or bad," she said. "They’re just things that happen to people, and when they do, there are measures that have to do with ensuring cleanliness.”

Juanmonino via Getty Images Where Muslims draw the line on cleanliness can seem random, Qamar said. Some wash so thoroughly before prayers that the mosque's bathrooms are covered in water but then refrain from brushing their teeth in fear the toothpaste would break their fast.

Qamar noted that there is no line in the Quran that directly says menstruating women cannot pray or fast, though there is a verse that prohibits having sex during a woman’s period at any point in the year. But Auston said the rule doesn't "come out of nowhere."

“Usually the Quran contains a general commandment, and then it’s almost always the case that the specific details of what that entails and how to handle it is generally contained in the hadith,” Auston said. Between those two sources primarily, Islamic jurists “extrapolate,” she said, to determine rules and customs.

Qamar rejected this explanation, however, saying even scholarly interpretations "come from very gendered perspectives of probably male scholars.”

But for Auston, there isn't a hidden narrative of women's oppression behind the rule. “Most women I know are not peeved about it," she said. "It’s just part of the hygiene regimen."

Not having to fast when I’m already physically depleted is something that I regard as a mercy.”

And rules surrounding menstruation aren’t unique to Islam, she noted. In strict interpretations of Judaism, women who are bleeding due to menstruation, miscarriage or after giving birth aren’t supposed to touch or sleep with their spouses. And they are expected to “purify” themselves with a ritual bath at the end of their menstrual cycle.

On another level, Auston added, both fasting and menstruating can be physically challenging. The rule is partly in place, she said, to ensure that women's bodies aren't unduly taxed.

“I’m physically depleted when I menstruate," Auston said. "I suffer from iron deficiency, especially while I’m menstruating, so not having to fast when I’m already physically depleted is something that I regard as a mercy.”

The break from fasting may be a 'God-given right,' but there's still a stigma.

Amani Al-Khatahtbeh, founder and editor-in-chief of media outlet MuslimGirl, takes a similar view on the restrictions for menstruating women during Ramadan Auston expressed. "It's nothing to be ashamed of," she told HuffPost, "because it's halal," or lawful. It should be viewed less as a prohibition, she said, and more as a welcome break.

But even in the context of God's "mercy," as Auston described it, a stigma remains. Joining menstruating women in abstaining from fasting and prayers are those who are ill, elderly, pregnant, breastfeeding, and traveling. In this context, Qamar said, the restriction on menstruating women seems to imply physical incapacity.

“Some say that not fasting during your period is this gift from God," she said, "but the reality is that not fasting is associated with weakness or inability.”

Al-Khatahtbeh echoed that there may a perception of weakness toward women who aren’t fasting or praying because they are menstruating. “There’s a stigma around it, unfortunately, that a woman is not practicing her religion even if it’s her God-given right because she’s menstruating. I think it’s very sexist.”

It's nothing to be ashamed of because it's halal.

Qamar related the prohibitions around menstruation to larger policing of the female body in some Muslim communities, saying she's been told things like, "Your butt is protruding too much," even within the women's section of the mosque.

“Growing up a lot of the time there was this idea that a woman has to cover her body because it’s distracting. That can generate self-hatred,” she told HuffPost.

Many Muslim women of course choose to cover themselves as part of their personal relationship to God, but for Qamar the pressure to do so within the mosque caused her to feel like something was wrong with her body.

'There's this public fascination with a woman's practice.'

This sense of women's bodies being on display is something that can be exacerbated during menstruation. And it isn’t just about women excusing themselves from prayers, Al-Khatahtbeh said.

There’s a common belief, for instance, that nail polish acts a barrier during the ritual cleansing Muslims do before prayers. Some believe that the water won’t actually reach the nail with the polish in the way, thus making the ablution invalid. “Some people joke that if a woman is wearing nail polish, then she must be menstruating,” Al-Khatahtbeh said. “It’s interesting but also sad how there’s this public fascination with a woman’s practice in that regard.”

When you’re 13 you don’t exactly want to tell your class you’re on your period.”

For some teenage girls, Qamar noted, this feeling of visibility is particularly excruciating. “A couple times I got my period during Ramadan I still didn’t eat at school because I didn’t want to explain to people who knew I was Muslim,” she said. “When you’re 13 you don’t exactly want to tell your class you’re on your period.”

Auston suggested that this anxiety over menstruation fades with age and isn't unique to the setting of Ramadan. "There’s self-consciousness about the whole process when you’re still kind of new at it," she said. "We all grapple with that no matter what the setting.”

Confronting the fear of missing out.

Self-consciousness aside, there's another concern that plagues some Muslim women during Ramadan: That they will miss out on the holy time when and if they get their period.

Ramadan entails a lot more than just fasting, much of which centers around the community as people come together to pray, break their fast and commiserate about the challenges of fasting.

Pacific Press via Getty Images Muslims break their fast at a large community iftar in Rome, Italy.

“For many Muslim women there's a sadness that comes from not being able to worship to the full extent that they eagerly want to,” Al-Khatahtbeh said.

One of Al-Khatahtbeh's first articles on MuslimGirl back in 2009 was about menstruation, called “Coping with your Period During Ramadan.” It served as a guide for Muslim women to remain connected to their spirituality even if they couldn’t fast for several days during the holy month.

“Just because they aren’t able to fast or pray doesn’t mean they’re going to be disengaged from the spirit of Ramadan,” Al-Khatahtbeh told HuffPost. “There are so many other practices of worship, like reciting the Quran, going to social events, and going to the mosque.”

Auston echoed that menstruating women can stay engaged by performing general supplication, a form of prayer that isn’t prohibited, and reading from the Quran, though interpretations vary over whether this is permitted.

"There are so many different ways that people can seek God's pleasure," she said.

To observe or not to observe.

HuffPost posed a question to Qamar, whose frustration around the restriction for menstruating women recently led her to pen a blog called "Menstruate and Self-Hate." If it bothered her to such a degree, then why follow the rule at all? Who would know she was menstruating if she chose to fast and pray during Ramadan?

Qamar laughed and admitted she'd asked herself that question, too. But she said the answer wasn't as simple as it might seem. Instead of leading her away from observance, her concerns have led her deeper into her faith, she said, inspiring her to seek out answers.

“My failure to abide by the checklist of ‘good Muslim girl’ is what propels me to remain vigilant about my religion and keep exploring for my own," she told HuffPost. "Those thoughts of ‘why don’t I just pray’ are the ones that have led me to do my own research and think more deeply. It has prompted me to try to explore my faith more, which has actually helped me come to terms with having a period, in general.”