Is there a link between the menstrual cycle and the lunar cycle?

Existe t'il un lien entre cycle menstruel et cycle lunaire ?

The lunar cycle lasts approximately 29.5 days, while the menstrual cycle averages 28 days. Coincidence? Not for everyone.

In fact, it has been hypothesized that the menstrual cycle and the lunar cycle were once synchronized.

In fact, the word menstruation comes from the ancient Greek "mensis" meaning month, itself derived from the cycles of the moon (called "mene" in ancient Greek). Amerindians used to refer to menstruation as "having your moons", as women in those days were said to menstruate together on the Full Moon or New Moon. During this period, they retreated to reconnect with nature. Whether in Greek mythology, Inca mythology or Chinese thought, a figure often represents both the moon and the female cycle or fertility. Indeed, according to some researchers, if the menstrual cycle is synchronized with the lunar cycle, the chances of reproduction are multiplied, as is the case with certain animals.

Our current lifestyles, disconnected from nature's rhythms, with schedules that are out of sync with the day/night cycle, but also the preponderance of artificial light and the advent of the pill, mean that the two cycles are no longer necessarily aligned. As a result, we're no longer in step with the natural rhythm, and our periods, once considered sacred, now seem all the more like a constraint.

Menstrual cycle and lunar cycle

The lunar cycle, like the menstrual cycle, is made up of 4 phases which can be linked and which also correspond to the 4 energies of life (birth, growth, blossoming, decline).

  • First Quarter (Maiden (or Virgo) or Spring phase): pre-ovulatory phase (D1 to D14, D1 being the first day of menstruation) when estrogen levels rise. Energy rises as the body regains its strength. This is the phase of renewal, conducive to new projects.
  • Full moon (Mother or Summer phase): ovulatory phase (D14). Energy and libido are at their peak. This is a phase in which you take care of others after focusing on yourself, and empathy is highly developed.
  • Last quarter (Enchantress or Autumn phase): premenstrual phase (D15 to D28). This phase is ideal for taking time out and resting, as gloom sets in and emotions explode in a need to externalize (corresponding to premenstrual syndrome).
  • New Moon (Witch or Winter phase): menstruation phase. The body gets rid of what it doesn't need to start a new cycle. A time of introspection, conducive to new resolutions. Need for sleep, time to slow down and renew energy.

    What do scientists say?

    Charles Darwin, father of the theory of evolution, already believed in the Moon's influence on menstruation, in parallel with the tidal cycle. But his successors don't necessarily agree. Indeed, a number of scientific studies have attempted to establish a link between the lunar and menstrual cycles, without much success. Similarly, no tangible link has been established for premenstrual syndrome. Studies have also been carried out into a possible increase in births on full-moon days. Here again, no increase in frequency has been observed.

    For scientists, there is a much more complex and interesting psychological, cultural and societal explanation. As human beings, we are not endowed with mechanical rationality, but with a memory that is selective according to our interests. We therefore notice more easily the events that are in line with our beliefs, which only reinforces them since we retain these events more easily and forget the others. What's more, we tend to get closer to people who hold the same beliefs as we do, which makes us adhere to them all the more.

    However, a study has just been published (on January 27, 2021 in the journal Science Advances) by researchers at the University of Würzburg in Germany, showing that there is indeed a link between the menstrual cycle and the lunar cycle. To demonstrate this, 22 women were asked to record their menstrual rhythm in a notebook. This data was then compared with the lunar cycle at the time. This showed that there was indeed a link.

    However, the study reveals that the Moon does not have an effect on all women, and that this effect diminishes with age. It also shows that exposure to one or more sources of artificial light at night, i.e. once the sun has set, has a positive effect on women's health. The later women go to bed and the more artificial light they are exposed to, the less synchronization there is between their cycle and the Moon. Nevertheless, the scientists remain aware that this study was not carried out on a large enough number of menstruating people, and hope to develop a future study using a smartphone application to conduct a larger, worldwide study.

      Nevertheless, whether or not you believe in lunar energies, taking an interest in them is a good way to reconnect with nature and yourself. You can use a lunar dial (a wheel divided into 4 for the 4 lunar phases) to mark your feelings (physical and emotional, but also your desires and needs) from the first day of your period to the end of your cycle. After a few months, you'll discover your own energies and be better able to adapt to them.

      Our organic cotton menstrual briefs are here to help you make the most of your cycles!

      Learn more about astrology and lunology

      The moon's cycle is known to have an impact on everyday life. The effects of the moon on our health are based on our mental and physical states. According to popular belief, the moon influences health, especially sleep and emotions. Some people point to the full moon as responsible for fatigue, while others claim that the new moon calms the nerves. In all cases, the moon and well-being are often cited together.

      Moon and childbirth are also linked, according to the idea that babies are born more often when the moon is full. Similarly, themoon's influence on births is also based on astrology. If you take the time to discover the different aspects of astrology linked to the moon, you'll surely be able to see the benefits.

      The art of lunology and the lunar cycle

      Lunology is the study of the phases of the moon throughout its cycle. Each phase has a different effect on our daily lives. For example, the new moon represents renewal, a stage in life when we start afresh with new projects and new goals. The gibbous moon is a period of reflection, when we need to take a step back from our actions. As for the balsamic moon (the moment when the night star becomes invisible once more), it's a time of awareness and rest, to await the start of the next cycle. All these phases are defined by the lunar calendar. According to certain beliefs, it's even possible to determine a baby's sex thanks to the lunar calendar.

      Discover our articles dedicated to lunology and the phases of the lunar cycle:

      Horoscopes (lunar, menstrual and sexual)

      Horoscopes are the study of the position of the stars and planets in relation to the astrological signs. Horoscopes come in many forms, such asmenstrual horoscopes. The stars can be used to determine how you should act according to the phase of your menstrual cycle. But that's not all! Possibly,horoscopes and childbirth are linked.

      There's also thesexual profile horoscope, which uses astrology to determine how you'll act in your intimate relationships. It's all about romance and sexuality. Each sign interacts in a different way according to its stars, and the sexual profile horoscope allows you to determine your sexual preferences, fantasies and desires. What's more, this tool lets you learn more about the horoscope's sexual accounting to better apprehend your future relationships.

      Discover all our content on the sexual profile of each zodiac sign:

      Aries woman Taurus woman Gemini woman
      Woman Cancer Leo Woman Woman Virgo
      Woman Libra Woman Scorpio Woman Sagittarius
      Woman Capricorn Woman Aquarius Pisces woman

      What's more, each phase of the lunar cycle has its own astrological significance. Indeed, although the sun sign is the most popular (the one you give when asked what your astrological sign is), there's also the moon sign. This is determined by the position of the Moon in relation to the zodiac at the time of birth.

      Check out our guides to the lunar cycle in astrology, and discover the profile of each lunar sign:

      Moon in Aries Moon in Taurus Gemini Moon
      Cancer Moon Leo Moon Moon in Virgo
      Libra moon Moon in Scorpio Moon in Sagittarius
      Moon in Capricorn Aquarius moon Pisces moon

      Chinese horoscopes

      Unlike Western horoscopes,Chinese horoscopes are an ancient astrological system (over 1000 years old), defined by the Chinese lunar calendar.

      Each Chinese zodiac sign is associated with personality traits. These include wood, fire, metal, water and earth. Chinese astrology is based on a 12-year cycle, with each year representing an animal. Thus, your Chinese zodiac sign may be the Water Hare, the Earth Rat or the Metal Dragon.

      According to the study of the stars in China, it is possible to establish a Chinese pregnancy calendar to determine the trials and joys encountered by a pregnant woman. The Chinese calendar can also be used to predict a baby's sex.

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      The information contained in the articles on is general information only. Although reviewed by health professionals, this information is not error-free, does not constitute health advice or consultation, and is not intended to provide a diagnosis or suggest a course of treatment. Under no circumstances may this information be used as a substitute for medical advice or consultation with a healthcare professional. If you have any questions, please consult your doctor.