Why do women’s periods sync with the periods of the women they live with?

Question

abc3643 · Accepted Answer

I asked Google Bard...

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MY PROMPT:

When a group of fertile women are cohabiting, why do their menses synchronize?

GOOGLE BARD RESPONSE, DRAFT 1:

The phenomenon of menstrual synchrony, in which the menstrual cycles of women who live together or spend a lot of time together become more similar over time, has been observed for centuries. However, the exact mechanism by which this occurs is still not fully understood.

One theory is that pheromones, or chemical messengers, play a role in menstrual synchrony. Pheromones can be released in sweat, saliva, and other bodily fluids. When women are in close proximity, they may be exposed to each other's pheromones, which could then influence their menstrual cycles.

Another theory is that social cues, such as the menstrual cycle of a close friend or roommate, can also influence a woman's own menstrual cycle. For example, if a woman sees that her friend is menstruating, she may start to feel more aware of her own menstrual cycle and may even start to experience symptoms earlier than she would have otherwise.

It is also possible that a combination of pheromones and social cues play a role in menstrual synchrony. More research is needed to determine the exact mechanism by which this phenomenon occurs.

It is important to note that menstrual synchrony is not a perfect phenomenon. Even if two women are living together and their cycles are becoming more similar, their periods will not always start on the same day. There is still a lot of variability in menstrual cycles, and it is impossible to predict exactly when a woman will start her period.

Despite the fact that menstrual synchrony is not a perfect phenomenon, it is a fascinating phenomenon that has been observed for centuries. More research is needed to determine the exact mechanism by which this phenomenon occurs, but it is clear that pheromones and social cues may play a role.

GOOGLE BARD RESPONSE, DRAFT 2:

The phenomenon of women's menstrual cycles synchronizing when they live together or spend a lot of time together is known as "menstrual synchrony" or the "McClintock effect." It was first proposed by Martha McClintock in 1971, who studied the menstrual cycles of 135 Wellesley College students. She found that the onset of menstruation was more similar among roommates than random pairings of women.

There are several possible explanations for menstrual synchrony. One is that women may be able to detect pheromones, or chemical signals, that are released by other women who are ovulating. These pheromones may trigger the release of luteinizing hormone (LH), which causes ovulation. Another possibility is that women may be more likely to have sex when they are around other women who are ovulating. This increased sexual activity may lead to more frequent ovulation, which could then lead to more synchronized menstrual cycles.

However, the evidence for menstrual synchrony is mixed. Some studies have found evidence to support the hypothesis, while others have not. It is possible that menstrual synchrony is a real phenomenon, but that it is not as strong as originally thought. It is also possible that menstrual synchrony is simply a coincidence.

More research is needed to determine whether or not menstrual synchrony is a real phenomenon and, if so, what causes it.

GOOGLE BARD RESPONSE, DRAFT 3:

The phenomenon of women's menstrual cycles synchronizing when they live together or spend a lot of time together is known as menstrual synchrony. It has been a topic of scientific research for decades, but the exact cause is still unknown.

One theory is that pheromones, or chemical messengers, play a role. Pheromones are released by the body and can affect the behavior of others. Some studies have shown that women who live together have higher levels of certain pheromones in their bodies, and that these levels fluctuate in sync with their menstrual cycles.

Another theory is that stress can cause menstrual synchrony. When women are under stress, their hormones can be affected, including the hormones that regulate their menstrual cycles. If a group of women are living or working in a stressful environment, their menstrual cycles may start to synchronize as a result.

It is also possible that genetics plays a role in menstrual synchrony. Some studies have shown that women who are genetically related are more likely to have synchronized menstrual cycles. This suggests that there may be a genetic component to the way that women's bodies respond to the hormones that regulate their menstrual cycles.

More research is needed to determine the exact cause of menstrual synchrony. However, the fact that it is a real phenomenon is supported by a number of scientific studies. If you are a woman who lives or works with other women, you may have noticed that your menstrual cycles start to line up over time. This is likely due to a combination of factors, including pheromones, stress, and genetics.

msc545 · Accepted Answer

The phenomenon of menstrual cycle synchronization, also known as the "menstrual synchrony" or the "McClintock effect," has been observed in several studies. However, the exact cause of this synchronization is still a topic of debate among scientists.

One theory is that the synchronization occurs due to pheromones, which are chemical signals released by one individual that can affect the physiology or behavior of another individual of the same species. Some researchers have suggested that pheromones produced by women during their menstrual cycle may influence the menstrual cycles of other women around them.

Another theory suggests that menstrual synchronization may be a result of social factors such as living in close proximity and spending a lot of time together. When women live together, they may be more likely to share experiences and environmental cues that could influence the timing of their menstrual cycles.

Not all studies have found evidence of menstrual synchronization. Some studies have found no significant evidence of menstrual cycle synchronization in women who live together. Therefore, more research is needed to understand the mechanisms behind menstrual cycle synchronization and whether it truly occurs in all cases.

Razp_Sorbet · Accepted Answer

They don't, it's a myth. The average menstrual cycle is 28 days long, so 14 days apart is the maximum amount of time two peoples periods could be apart. Since periods last around 5 days there is a big chance for overlapping. It's just all chance a coincidence.

Puppystarfish23 · Accepted Answer

I have no idea but I grew up in house with 4 other women and it always used to happen I also used to sycn with my friends too and even though I don't get my period as often now I still sycn with work friends

Telekinetic-Potato · Answer

I heard that it happens because it's the body's way of keeping the woman in competition for the men the other woman might be going after.

Say you all live in a village together and there's only so many men, you won't be disqualified from having a child with one of the men the other woman are after because of your period. Where if the period were to happen off sync, you might be left with less deserible choices.

I don't know how well that logic holds but I always thought it was an interesting theory.

D_Bone_Steak · Answer

It's probably nature's way of making sure girls' night out will be matching ovulation. What better way to try and get girls pregnant by nature than to make them all slut out at the same time?

Although I have picked up a lot of girls going freaky and the period stuff was going on... I usually left blood hand prints on the wall after fishing the condom that came off in their vagina out. Those are caveman hand prints and are historical evidence that I was there.

Ik bun vulgaris magisralis!

Moose304 · Answer

I asked my 47-year-old girlfriend about this today. Her reply was it is much ado about nothing. What she told me though was it actually happened to her after her divorce. She moved in with a close friend who was divorced that was living with her then-17-year-old daughter. This does not happen in weeks. It sometimes takes a year or so. My girlfriend who since she was a teenager has tracked her periods started to notice she was not always doing the 28 days. Over about 18 months she was needing feminine products at the same time the other two females were. Being a male that lives alone I never really paid much attention to this. What I do know is a woman's Menstrual cycle is driven by hormones. Anything that can interfere with the production of these hormones can affect the timing. This is an interesting question.

Cubus · Answer

There are two theories

One that if women feels that another women is fertile (can get pregnant) her body would enforce the menstrual cycle to be fertile as well, because if both get pregnant at the same time, and both have children at the same time, it would be easier to raise them up together.

Second is that if women feels that another women is fertile (can get pregnant) her body would enforce the menstrual cycle to be fertile as well, because she doesn't want to "miss the chance" to get pregnant. It's about rivalry - your body you to be impregnated and not the other woman (it's Mother Nature's way to make us survive as a species).

CupcakeTheDestroyer · Answer

It mainly depends on the estrogen levels. As bodies come closer to others to experience their hormones and pheromones, chemicals tend to shift around and the body takes in information to say “oh, you have that much estrogen? Then we better expel the egg at the same time, we need more estrogen like you.” Which is kind of what happens on a very basic level

lightbulb27 · Answer

fascinating, I would assume this is true if you have two or more females in the same space.

If this is the case, why don't all females synch... like if they work together, do they fall into synch?

My theory is... bacteria gets spread amoung them and that influences timing. We should immediately start teaching this theory as fact to 8th graders and see if they can prove it.

razelove · Answer

So you can help each other wash the bloody rags off down by the river. Lest one of you travel away from the pack alone and get eatten by a coyote.

Who knows, there are reasons why it could be advantageous or disadvantageous. Maybe it's a coincidence, I mean, if you're a woman with cysts or something it won't matter if you sync up and have a cycle that's off by a day or more shorter or longer.

It would be a constant cycle of "syncing"

AviatorTom · Answer

Science will tell you it's a myth but several women, including my ex-wife if 20 years, have told me it's true.

Some scientists have the unproven theory is that it's Mother Nature's way of enhancing reproductive competition by making all the women sexually available at the same time.

FunkyMonkee · Answer

It's to do with hormones and smells. One has her period and others that she's around unknowingly pick up on the hormones she exudes at that time of the month, as well as the smells of it and their own body falls more and more into sync with hers. Women that spend a lot of time together at work have that, too.

Bully-O-Frog · Answer

Hormones/pheromones and similar substances can be sensed subconsciously by other people based on changes they cause in the body. It's an evolutionary trait that helps with pack/tribal bonding.

Kind of how some animals will reject other animals of the same species, often the babies, by way of smell? Exactly that but in humans. Its more complex than just smells though.

petitedollbabee · Answer

Pretty sure it’s just a myth. I’ve never had my period sync with anyone else’s. And my family is mostly women.

Paige90 · Answer

I don't live with a girl but mine does start with various girls that are friends but not every month.

Gent207-2 · Answer

Scientifically this has been provenance psychosomatic and not really a thing

RoastedToast · Answer

Synchronization theory or spontaneous synchronous in nature. Look I have no idea last I checked a woman is not a pendulum so I don't know I'm just pointing out the rabbit hole

kellytheman · Answer

I think if they live together that might have the same lifestyle and do a lot of the same things. I not sure how periods become sync up but I am a guy I don't know anything.

Mimi_758 · Answer

Yes it those me and my friends have the same periods because we live together :)

Manuel2 · Answer

To save time on going fighting and you find at least there are plenty of tampons when all due. Also when they are ovalulating, the sex parties ate great

mstoxicprincess · Answer

men’s behavior always gets based on woman’s attitude … they say a happy wife is a happy life for that reason :) it’s all up to the girls

SmartAlic78 · Answer

There periods sync with other women because they became very close they talk to each other they know the girl code since they are both girls And like to be fronds and talk about boys

Anonymous · Answer

Someone come sync with me. Im tired of being late

Anonymous · Answer

To compete with them and if they win, feel good about themselves

peedy · Answer

Im a man so I have no idea maybe so their boyfriends can go drinking together

Minahh · Answer

No it is synchronized with the moon https://www. science. org/doi/10.1126/sciadv. abe1358

Rachelle__1987 · Answer

I not sure but cannot say mine ever did and I lived with two females ( mom and sister ) but I have pcos so never had normal periods

Anonymous · Answer

Do they? Certainly it can happen since it lasts almost a week you only have 3 weeks without so they can line up eventually since they change over time

Britney04 · Answer

My girlfriend and mine same why it happened that way I don't know.

Anonymous · Answer

I'm guessing it's so they can all get fucked and impregnated at the same time by the same guys. Like an orgy. It's possible humans used to reproduce like that.

Anonymous · Answer

At some point will be in sync, but not for long term due to timing differences among girls.

Anonymous · Answer

To prevent the guy you live with from getting everyone pregnant.

Finchie40 · Answer

It’s shark week sharks usually stick together 😜

Apple1996 · Answer

I've heard that is a myth

Makeushiver · Answer

universe just seems to work that way

Spade_01 · Answer

Does it? Interesting phenomenon 🧐

Jennz6 · Answer

Mine doesn’t sync with my girlfriend’s

Anonymous · Answer

for competition to get pregnant first.

boobliker · Answer

to stop the men from arguing

CT_CD · Answer

Mine doesn’t

Anonymous · Answer

My daughters and mine are.

Anonymous · Answer

Does that really happen?

siseñor · Answer

pheromones

Twalli · Answer

They don't

Preeti161101 · Answer

Out of information

LovrUFFAllls · Answer

They do?

Anonymous · Answer

Lol seriously 😳?

Why do women’s periods sync with the periods of the women they live with?

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Why do women’s periods sync with the periods of the women they live with?

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Do all women behave similar during their period?

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