# Does menstruation serve a social purpose in humans, perhaps some animals?

**URL:** <https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821>\
**Category:** In My Humble Opinion\
**Created:** [October 25, 2017, 4:45pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821 "2017-10-25T16:45:47Z")\
**Posts on this page:** 20\
**Page:** 2

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**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\
**Post date:** [October 25, 2017, 8:33pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/21 "2017-10-25T20:33:56Z")

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Men produce all the same bodily wastes as an infant (OK, so they are more likely to vomit up partly digested beer than milk, in my experience), why would women having an extra one not produced by babies help in dealing with baby waste? 😕

It’s debatable that dealing with menstrual fluid can help in dealing with blood, but, well, I’m not a parent, but I didn’t think babies were supposed to bleed all that often.

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**Author:** ![Qadgop\_the\_Mercotan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/qadgop_the_mercotan/32/83_2.png) [@Qadgop\_the\_Mercotan](https://boards.straightdope.com/u/Qadgop_the_Mercotan)\
**Post date:** [October 25, 2017, 9:34pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/22 "2017-10-25T21:34:37Z")

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> [@QuickSilver](#):
>
> Nah. I’ve lost the mood.

Mood’s a thing for cattle and love play, not posting!

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**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\
**Post date:** [October 25, 2017, 9:46pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/23 "2017-10-25T21:46:19Z")

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> [@kanicbird](#):
>
> Does menstruation serve a social purpose in humans, perhaps even some animals.
> 
> (In humans) monthly (cyclic) bleeding, and dealing with fluid discharge on a regular basis, well dealing with anything on a regular basis , tends to desensitizes a person from dealing with unpleasant things. It the dealing with monthly periods and somehow programming women to be the ones to be able to better handle the bodily discharges of infants (and thus be considered the natural consideration for primary guardian when a dispute arises?) , and perhaps even extended to some vocations like traditionally nursing, so sort of desensitizing to such discharges allowing they to do certain things more comfortably then males who don’t have to deal with this?

I was home with my son for a year, so I did most of the diapers, but when my husband was home, we did “Rock, paper, scissors.” I almost always won. He didn’t seem to realize it, but he always threw what would have beat whatever he threw the last time, and as long as I could remember whatever he’d done two hours ago, or yesterday, I’d win.

For the record, though, he was the first one to change our son’s diaper, of the two of us, in the hospital.

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**Author:** ![Maggie\_the\_Ocelot](https://avatars.discourse-cdn.com/v4/letter/m/df705f/32.png) [@Maggie\_the\_Ocelot](https://boards.straightdope.com/u/Maggie_the_Ocelot)\
**Post date:** [October 25, 2017, 9:55pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/24 "2017-10-25T21:55:15Z")

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“Omnipresent”

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**Author:** ![Leaffan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leaffan/32/299_2.png) [@Leaffan](https://boards.straightdope.com/u/Leaffan)\
**Post date:** [October 25, 2017, 10:13pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/25 "2017-10-25T22:13:42Z")

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Until I had kids, I had never changed a diaper in my life.

And then it just came naturally and instincually. It never bothered me in the least.

Although… at my daughter’s birthday party, when she was turning 3, one of her invitees shit his pants. OMG I gagged and gagged and almost puked cleaning him up.

Why is it different when it’s your own kid?

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**Author:** ![RivkahChaya](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/rivkahchaya/32/8919_2.png) [@RivkahChaya](https://boards.straightdope.com/u/RivkahChaya)\
**Post date:** [October 25, 2017, 10:19pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/26 "2017-10-25T22:19:33Z")

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> [@Leaffan](#):
>
> Until I had kids, I had never changed a diaper in my life.
> 
> And then it just came naturally and instincually. It never bothered me in the least.
> 
> Although… at my daughter’s birthday party, when she was turning 3, one of her invitees shit his pants. OMG I gagged and gagged and almost puked cleaning him up.
> 
> Why is it different when it’s your own kid?

I work in a preschool. It’s also different when you are getting paid to do it.

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**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\
**Post date:** [October 25, 2017, 11:04pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/27 "2017-10-25T23:04:27Z")

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I don’t know about a social purpose, per se, unless you count when I am pms-ing, I purposely want to kill people. And I assume blood would be let, if that is what you mean!

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**Author:** ![HMS\_Irruncible](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hms_irruncible/32/7394_2.png) [@HMS\_Irruncible](https://boards.straightdope.com/u/HMS_Irruncible)\
**Post date:** [October 25, 2017, 11:12pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/28 "2017-10-25T23:12:22Z")

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> [@kanicbird](#):
>
> Does menstruation serve a social purpose in humans, perhaps even some animals.
> 
> (In humans) monthly (cyclic) bleeding, and dealing with fluid discharge on a regular basis, well dealing with anything on a regular basis , tends to desensitizes a person from dealing with unpleasant things. It the dealing with monthly periods and somehow programming women to be the ones to be able to better handle the bodily discharges of infants (and thus be considered the natural consideration for primary guardian when a dispute arises?) , and perhaps even extended to some vocations like traditionally nursing, so sort of desensitizing to such discharges allowing they to do certain things more comfortably then males who don’t have to deal with this?

I think all of that is probably… not true.

To me, a much more interesting question is why it more or less lines up with the lunar month. It might be coincidence, but I think it would be a big help for a woman trying to get pregnant (or avoid it). I mean not a perfect gauge, but better than the alternative of remembering it was 17 days since the last cycle.

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**Author:** ![silenus](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/silenus/32/166_2.png) [@silenus](https://boards.straightdope.com/u/silenus)\
**Post date:** [October 25, 2017, 11:13pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/29 "2017-10-25T23:13:59Z")

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> [@Machine\_Elf](#):
>
> “Nevertheless, he persisted.” 😃
> 
> I’m not looking for a synonym for “incessant.” Instead, I’m questioning the apparent belief held by **Chicken Fingers** that men exist in a constant state of ejaculation.

Do you _remember_ being 14?

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**Author:** ![Chicken\_Fingers](https://avatars.discourse-cdn.com/v4/letter/c/51bf81/32.png) [@Chicken\_Fingers](https://boards.straightdope.com/u/Chicken_Fingers)\
**Post date:** [October 26, 2017, 2:32pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/30 "2017-10-26T14:32:37Z")

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> [@Machine\_Elf](#):
>
> “Nevertheless, he persisted.” 😃
> 
> I’m not looking for a synonym for “incessant.” Instead, I’m questioning the apparent belief held by **Chicken Fingers** that men exist in a constant state of ejaculation.

I was exaggerating, slightly, but hey, it’s all about perspective. I’m a woman in a house of men. How do you people get anything else done?

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**Author:** ![ZonexandScout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zonexandscout/32/544_2.png) [@ZonexandScout](https://boards.straightdope.com/u/ZonexandScout)\
**Post date:** [October 26, 2017, 2:57pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/31 "2017-10-26T14:57:36Z")

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I _think_ that I understand the OP’s question, so I’ll say “no, not in the sense you mean.”

For most species, the oestrus cycle is closely linked to seasonal variations in the food supply,temperature, migration patterns, and other external factors. In humans, these are relatively less important when a reliable food source is available. Once humans began engaging in agriculture and domesticating livestock, the seasonal variations became much less important. Pair bonding, due to the exceptionally long period required to raise a child, increased in importance. A shorter oestrus cycle certainly contributes to pair bonding, though there many well-known situations where species pair-bond for live while retaining an annual/season oestrus.

Human menstruation is an outcome of a short oestrus cycle. There are many other factors involved, but this is a simple way of viewing it.

It may also be worth pointing out that menses are closely tied to body weight and fat. Insufficient body weight or fat can easily result in amenorrhoea.

TL;DR: Do women have monthly menses in order to prepare them for other gross things? No.

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**Author:** ![ZonexandScout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/zonexandscout/32/544_2.png) [@ZonexandScout](https://boards.straightdope.com/u/ZonexandScout)\
**Post date:** [October 26, 2017, 2:58pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/32 "2017-10-26T14:58:45Z")

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I _think_ that I understand the OP’s question, so I’ll say “no, not in the sense you mean.”

For most species, the oestrus cycle is closely linked to seasonal variations in the food supply,temperature, migration patterns, and other external factors. In humans, these are relatively less important when a reliable food source is available. Once humans began engaging in agriculture and domesticating livestock, the seasonal variations became much less important. Pair bonding, due to the exceptionally long period required to raise a child, increased in importance. A shorter oestrus cycle certainly contributes to pair bonding, though there many well-known situations where species pair-bond for life while retaining an annual/season oestrus.

Human menstruation is an outcome of a short oestrus cycle. There are many other factors involved, but this is a simple way of viewing it.

It may also be worth pointing out that menses are closely tied to body weight and fat. Insufficient body weight or fat can easily result in amenorrhoea.

TL;DR: Do women have monthly menses in order to prepare them for other gross things? No.

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**Author:** ![Lamia](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Lamia](https://boards.straightdope.com/u/Lamia)\
**Post date:** [October 26, 2017, 3:43pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/33 "2017-10-26T15:43:49Z")

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> [@HMS\_Irruncible](#):
>
> To me, a much more interesting question is why it more or less lines up with the lunar month. It might be coincidence, but I think it would be a big help for a woman trying to get pregnant (or avoid it). I mean not a perfect gauge, but better than the alternative of remembering it was 17 days since the last cycle.

It _doesn’t_ line up with the lunar month. The average menstrual cycle is about a month long, but that varies considerably from person to person and can vary even for the same woman at different times. Anecdotally I’d say there doesn’t seem to be any connection between the phases of the moon and when a woman is menstruating, and I went to an all-female college where friends would mention being on the rag pretty casually. When [Uncle Cecil covered this topic](http://www.straightdope.com/columns/read/1348/whats-the-link-between-the-moon-and-menstruation) a number of years back it sounded like there was at best limited evidence suggesting a correlation for some women:

> [@Cecil Adams](#):
>
> Efforts to turn up similar patterns in humans have had unimpressive results, however. Several researchers over the years have claimed to detect lunar rhythms in menstrual onset and such; others see nothing. Biologist Winnifred Cutler, in a 1980 paper, found that 40 percent of women in a random sample showed “a preponderance of menses onsets in the light half-cycle of the month” (the two weeks centered on the full moon). To me this suggests 60 percent of the women _didn’t_ show any coincidence. If there really is a moon-menstruation link, you couldn’t prove it by me.

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**Author:** ![Maurie](https://avatars.discourse-cdn.com/v4/letter/m/df788c/32.png) [@Maurie](https://boards.straightdope.com/u/Maurie)\
**Post date:** [October 26, 2017, 6:39pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/34 "2017-10-26T18:39:47Z")

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[

> [@Lamia](#):
>
> It _doesn’t_ line up with the lunar month. The average menstrual cycle is about a month long, but that varies considerably from person to person and can vary even for the same woman at different times. Anecdotally I’d say there doesn’t seem to be any connection between the phases of the moon and when a woman is menstruating, and I went to an all-female college where friends would mention being on the rag pretty casually. When [Uncle Cecil covered this topic](http://www.straightdope.com/columns/read/1348/whats-the-link-between-the-moon-and-menstruation) a number of years back it sounded like there was at best limited evidence suggesting a correlation for some women:

I don’t necessarily agree with him, but I don’t think he meant that all women menstruate in unison or that the moon in some way controls menstruation. I read it as just him finding it interesting that the average menstrual cycle is approximately the same length as the lunar month, and pondering whether that fact may have been useful to some women in tracking their cycle.

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**Author:** ![Lamia](https://avatars.discourse-cdn.com/v4/letter/l/8e7dd6/32.png) [@Lamia](https://boards.straightdope.com/u/Lamia)\
**Post date:** [October 26, 2017, 11:30pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/35 "2017-10-26T23:30:33Z")

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> [@Maurie](#):
>
> [I don’t necessarily agree with him, but I don’t think he meant that all women menstruate in unison or that the moon in some way controls menstruation. I read it as just him finding it interesting that the average menstrual cycle is approximately the same length as the lunar month, and pondering whether that fact may have been useful to some women in tracking their cycle.

Yes, I got that **HMS Irruncible** believes there’s some significance to the human menstrual cycle being roughly the same length as the lunar month. But as the Straight Dope column I linked to says (quoting astronomer George O. Abell) “The moon’s cycle of phases is 29.53 days, while the human female menstrual cycle averages 28 days (although it varies among women and from time to time with individual women); this is hardly even a good coincidence!”

Google tells me the average \*range \*for adult women’s menstrual cycles is 21-35 days, and for teenagers is 21-45 days ([womenshealth.gov](https://www.womenshealth.gov/menstrual-cycle)). There presumably are _some_ women whose cycle is typically 29 days-and-change, but even they’d have to be pretty regular for the phases of the moon to be helpful in tracking their cycle in the long term.

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**Author:** ![Max\_Torque](https://avatars.discourse-cdn.com/v4/letter/m/e9bcb4/32.png) [@Max\_Torque](https://boards.straightdope.com/u/Max_Torque)\
**Post date:** [October 27, 2017, 4:44pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/36 "2017-10-27T16:44:23Z")

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Why would it be more of a “prepare to deal with gross things!” than just an obvious indicator of fertility? If it has a purpose at all, that seems to me to be the best one.

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**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\
**Post date:** [October 27, 2017, 4:52pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/37 "2017-10-27T16:52:53Z")

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> [@Max\_Torque](#):
>
> Why would it be more of a “prepare to deal with gross things!” than just an obvious indicator of fertility?

The actual “bleeding” part is just getting rid of waste products. Menstruation is no more meant to say “hey, I’m fertile!” than pooping is meant to say “hey, get ready for anal!”.

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**Author:** ![Quartz](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/quartz/32/267_2.png) [@Quartz](https://boards.straightdope.com/u/Quartz)\
**Post date:** [October 27, 2017, 7:41pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/38 "2017-10-27T19:41:35Z")

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Can I reverse the OP? Has a social purpose been constructed from menstruation? I’m thinking of the menstrual huts of certain cultures, for instance, which must allow women man-free time to talk, work, etc.

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**Author:** ![Warm\_blood](https://avatars.discourse-cdn.com/v4/letter/w/df705f/32.png) [@Warm\_blood](https://boards.straightdope.com/u/Warm_blood)\
**Post date:** [October 30, 2017, 9:13pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/39 "2017-10-30T21:13:44Z")

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> [@Darren\_Garrison](#):
>
> The actual “bleeding” part is just getting rid of waste products. Menstruation is no more meant to say “hey, I’m fertile!” than pooping is meant to say “hey, get ready for anal!”.

Do you understand the purpose of menstruation? Humans aren’t biologically wired to have anal sex, so I don’t see how this analogy makes sense in your mind.

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**Author:** ![Beckdawrek](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beckdawrek/32/3647_2.png) [@Beckdawrek](https://boards.straightdope.com/u/Beckdawrek)\
**Post date:** [October 30, 2017, 11:02pm UTC](https://boards.straightdope.com/t/does-menstruation-serve-a-social-purpose-in-humans-perhaps-some-animals/799821/40 "2017-10-30T23:02:56Z")

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Bleeding monthly means you have a uterus that prepares itself on a regular cycle to have a pregnancy. While pregnant your cycle is suspended until you give birth. Breastfeeding said infant sometimes prevents you from becoming pregnant again. ( Don’t count on that though, I have one grandson who challenged that rule).

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