This post has been self-published on Youth Ki Awaaz by Bleed Eco. Just like them, anyone can publish on Youth Ki Awaaz.

Does Your Period Tend To Sync With Your Friends, Too?

More from Bleed Eco

When I was in my undergraduate years, my best friends and I never had trouble keeping track of our periods. We knew that once one of us starts menstruating, we will follow the lead. Like that scene from the, No Strings Attached (2011) when Ashton Kutcher enters the room in the girls’ apartment and looking at them holding hot water bags to their abdomen exclaims “You’re all on the same cycle!”?

Representational image.

In fact, when I told about this weird phenomenon to someone I knew, I was told that it goes on to show the closeness or bond shared among menstruators. I found out quite late that is it popularly known as the McClintock Effect or the phenomenon of menstrual synchrony, an alleged process according to which women (I prefer to think all menstruators) living in close proximity tends to experience the onset of their menstrual cycles at the same time.

The idea has been generated by the pheromone effect. Pheromones are chemicals released by animals that influence the behaviour of others of the same species, and a considerable amount of literature exists to show that among animals and insects, pheromones can affect hormonal behaviours.

However, no existing study of the pheromone effect impacting humans exists to this date. In fact, after the McClintock Effect first came to be widely regarded in 1971, researchers went on to argue about the several methodological flaws in the study itself and 2013 successfully concluded that menstrual synchrony is not likely to exist.

How Credible Are These Theories?

In fact, with the widespread use of period tracking applications, the McClintock conclusion has come to be completely discarded. Researchers have also investigated the lunar phases and their supposed power to push around a menstruator’s period cycle. After all, the menstrual cycle has been traditionally believed to be in sync with the lunar cycle. However, no creditable research has been found to support these old wives’ tales.

Most scientists have shown that one menstruator living with another for a certain long time, then mathematically their period cycles are supposed to coincide a couple of times during the year. Others have shown that people living in close proximity experience the same routines – diet, sleep schedules, exercise and shared stressors – which could possibly have led to a shared menstrual habit as well. However, there are other, more important and scientific things that go on to affect one’s period cycle, like:

  1. Birth Control Pills: They alter the levels of estrogen and progesterone and can significantly meddle with one’s menstrual cycle.
  2. Stress or Anxiety: Mental Health, especially constant worrying, can lead to fluctuations in one’s period cycle.
  3. Chronic Illnesses: If a menstruator is undergoing a certain illness for which they are under medication, then their period cycle might fluctuate. In fact, PCOD is one of the many diseases that sustain irregularity in periods and an inconstant period cycle.
  4. Anorexia/Bulimia: Highly restrictive control over calorie intake can also affect one’s period cycle.

BBC News reports Alexandra Alvergne, an associate professor in biocultural anthropology at the University of Oxford saying, “  As humans, we always like exciting stories. We want to explain what we observe by something that is meaningful. And the idea that what we observe is due to chance or randomness is just not as interesting.”

A 2006 study had successfully shown that among 186 women living in groups in a dorm in China, period syncing was merely a mathematical coincidence while a smaller study conducted in 2017 has shown that almost 44% of the participants experienced period syncing, even the common period symptoms like menstrual migraine coincided. Does this then show that menstruators might be influencing each other’s periods in ways beyond the timing of their menstruation? To date, researchers aren’t quite sure.

How Community Dialogue Can Improve Indian Women's Menstrual Health
Periods are your personal experiences, never believe anything else!

Menstrual synchrony is and will always be hard to prove because period cycles are not uniform across individuals and populations. They may vary with respect to various irregularities and factors both physical and external. Many popularly believe that the reason menstruators believe in the concept is that they feel comforted to think that someone close to them is undergoing the exact same process and can relate with their mood, cravings and bodily discomfort.

Finally, syncing one’s periods might not have any scientific evidence to back it up but it is absolutely okay to believe in the experience of being on your period and feeling the pre-menstrual syndromes, the skin breakouts and the menstrual cramps, they are your experiences, they are real and never believe anything otherwise.

Written by Ahendrila Goswami

You must be to comment.

More from Bleed Eco

Similar Posts

By Anjali joseph

By Ria Gupta

By IMPRI Impact and Policy Research Institute

Wondering what to write about?

Here are some topics to get you started

Share your details to download the report.

We promise not to spam or send irrelevant information.

Share your details to download the report.

We promise not to spam or send irrelevant information.

An ambassador and trained facilitator under Eco Femme (a social enterprise working towards menstrual health in south India), Sanjina is also an active member of the MHM Collective- India and Menstrual Health Alliance- India. She has conducted Menstrual Health sessions in multiple government schools adopted by Rotary District 3240 as part of their WinS project in rural Bengal. She has also delivered training of trainers on SRHR, gender, sexuality and Menstruation for Tomorrow’s Foundation, Vikramshila Education Resource Society, Nirdhan trust and Micro Finance, Tollygunj Women In Need, Paint It Red in Kolkata.

Now as an MH Fellow with YKA, she’s expanding her impressive scope of work further by launching a campaign to facilitate the process of ensuring better menstrual health and SRH services for women residing in correctional homes in West Bengal. The campaign will entail an independent study to take stalk of the present conditions of MHM in correctional homes across the state and use its findings to build public support and political will to take the necessary action.

Saurabh has been associated with YKA as a user and has consistently been writing on the issue MHM and its intersectionality with other issues in the society. Now as an MHM Fellow with YKA, he’s launched the Right to Period campaign, which aims to ensure proper execution of MHM guidelines in Delhi’s schools.

The long-term aim of the campaign is to develop an open culture where menstruation is not treated as a taboo. The campaign also seeks to hold the schools accountable for their responsibilities as an important component in the implementation of MHM policies by making adequate sanitation infrastructure and knowledge of MHM available in school premises.

Read more about his campaign.

Harshita is a psychologist and works to support people with mental health issues, particularly adolescents who are survivors of violence. Associated with the Azadi Foundation in UP, Harshita became an MHM Fellow with YKA, with the aim of promoting better menstrual health.

Her campaign #MeriMarzi aims to promote menstrual health and wellness, hygiene and facilities for female sex workers in UP. She says, “Knowledge about natural body processes is a very basic human right. And for individuals whose occupation is providing sexual services, it becomes even more important.”

Meri Marzi aims to ensure sensitised, non-discriminatory health workers for the needs of female sex workers in the Suraksha Clinics under the UPSACS (Uttar Pradesh State AIDS Control Society) program by creating more dialogues and garnering public support for the cause of sex workers’ menstrual rights. The campaign will also ensure interventions with sex workers to clear misconceptions around overall hygiene management to ensure that results flow both ways.

Read more about her campaign.

MH Fellow Sabna comes with significant experience working with a range of development issues. A co-founder of Project Sakhi Saheli, which aims to combat period poverty and break menstrual taboos, Sabna has, in the past, worked on the issue of menstruation in urban slums of Delhi with women and adolescent girls. She and her team also released MenstraBook, with menstrastories and organised Menstra Tlk in the Delhi School of Social Work to create more conversations on menstruation.

With YKA MHM Fellow Vineet, Sabna launched Menstratalk, a campaign that aims to put an end to period poverty and smash menstrual taboos in society. As a start, the campaign aims to begin conversations on menstrual health with five hundred adolescents and youth in Delhi through offline platforms, and through this community mobilise support to create Period Friendly Institutions out of educational institutes in the city.

Read more about her campaign. 

A student from Delhi School of Social work, Vineet is a part of Project Sakhi Saheli, an initiative by the students of Delhi school of Social Work to create awareness on Menstrual Health and combat Period Poverty. Along with MHM Action Fellow Sabna, Vineet launched Menstratalk, a campaign that aims to put an end to period poverty and smash menstrual taboos in society.

As a start, the campaign aims to begin conversations on menstrual health with five hundred adolescents and youth in Delhi through offline platforms, and through this community mobilise support to create Period Friendly Institutions out of educational institutes in the city.

Find out more about the campaign here.

A native of Bhagalpur district – Bihar, Shalini Jha believes in equal rights for all genders and wants to work for a gender-equal and just society. In the past she’s had a year-long association as a community leader with Haiyya: Organise for Action’s Health Over Stigma campaign. She’s pursuing a Master’s in Literature with Ambedkar University, Delhi and as an MHM Fellow with YKA, recently launched ‘Project अल्हड़ (Alharh)’.

She says, “Bihar is ranked the lowest in India’s SDG Index 2019 for India. Hygienic and comfortable menstruation is a basic human right and sustainable development cannot be ensured if menstruators are deprived of their basic rights.” Project अल्हड़ (Alharh) aims to create a robust sensitised community in Bhagalpur to collectively spread awareness, break the taboo, debunk myths and initiate fearless conversations around menstruation. The campaign aims to reach at least 6000 adolescent girls from government and private schools in Baghalpur district in 2020.

Read more about the campaign here.

A psychologist and co-founder of a mental health NGO called Customize Cognition, Ritika forayed into the space of menstrual health and hygiene, sexual and reproductive healthcare and rights and gender equality as an MHM Fellow with YKA. She says, “The experience of working on MHM/SRHR and gender equality has been an enriching and eye-opening experience. I have learned what’s beneath the surface of the issue, be it awareness, lack of resources or disregard for trans men, who also menstruate.”

The Transmen-ses campaign aims to tackle the issue of silence and disregard for trans men’s menstruation needs, by mobilising gender sensitive health professionals and gender neutral restrooms in Lucknow.

Read more about the campaign here.

A Computer Science engineer by education, Nitisha started her career in the corporate sector, before realising she wanted to work in the development and social justice space. Since then, she has worked with Teach For India and Care India and is from the founding batch of Indian School of Development Management (ISDM), a one of its kind organisation creating leaders for the development sector through its experiential learning post graduate program.

As a Youth Ki Awaaz Menstrual Health Fellow, Nitisha has started Let’s Talk Period, a campaign to mobilise young people to switch to sustainable period products. She says, “80 lakh women in Delhi use non-biodegradable sanitary products, generate 3000 tonnes of menstrual waste, that takes 500-800 years to decompose; which in turn contributes to the health issues of all menstruators, increased burden of waste management on the city and harmful living environment for all citizens.

Let’s Talk Period aims to change this by

Find out more about her campaign here.

Share your details to download the report.

We promise not to spam or send irrelevant information.

A former Assistant Secretary with the Ministry of Women and Child Development in West Bengal for three months, Lakshmi Bhavya has been championing the cause of menstrual hygiene in her district. By associating herself with the Lalana Campaign, a holistic menstrual hygiene awareness campaign which is conducted by the Anahat NGO, Lakshmi has been slowly breaking taboos when it comes to periods and menstrual hygiene.

A Gender Rights Activist working with the tribal and marginalized communities in india, Srilekha is a PhD scholar working on understanding body and sexuality among tribal girls, to fill the gaps in research around indigenous women and their stories. Srilekha has worked extensively at the grassroots level with community based organisations, through several advocacy initiatives around Gender, Mental Health, Menstrual Hygiene and Sexual and Reproductive Health Rights (SRHR) for the indigenous in Jharkhand, over the last 6 years.

Srilekha has also contributed to sustainable livelihood projects and legal aid programs for survivors of sex trafficking. She has been conducting research based programs on maternal health, mental health, gender based violence, sex and sexuality. Her interest lies in conducting workshops for young people on life skills, feminism, gender and sexuality, trauma, resilience and interpersonal relationships.

A Guwahati-based college student pursuing her Masters in Tata Institute of Social Sciences, Bidisha started the #BleedwithDignity campaign on the technology platform, demanding that the Government of Assam install
biodegradable sanitary pad vending machines in all government schools across the state. Her petition on has already gathered support from over 90000 people and continues to grow.

Bidisha was selected in’s flagship program ‘She Creates Change’ having run successful online advocacy
campaigns, which were widely recognised. Through the #BleedwithDignity campaign; she organised and celebrated World Menstrual Hygiene Day, 2019 in Guwahati, Assam by hosting a wall mural by collaborating with local organisations. The initiative was widely covered by national and local media, and the mural was later inaugurated by the event’s chief guest Commissioner of Guwahati Municipal Corporation (GMC) Debeswar Malakar, IAS.

Sign up for the Youth Ki Awaaz Prime Ministerial Brief below