Is period syncing true?

Do mothers and daughters really sync?

Quick summary

• Period syncing is the belief that people who menstruate will align their cycles when spending time together.
• However, there is little scientific evidence supporting period syncing, and most experts consider it a myth.
• Using period tracking tools can help them better understand their own patterns rather than relying on others' cycles.

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Let’s explore an interesting concept you may have heard about – period syncing, or the idea that menstruators’ cycles align when they spend a lot of time together.

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What’s the idea behind period syncing?

This concept dates back to the 1970s when researchers suggested that pheromones (natural chemicals our bodies emit) could influence each other, leading to synchronised menstrual cycles. Recently, we've noticed a resurgence on social media and it's become a bit of a TikTok trend.

In simpler terms, the theory is that if your teen spends significant time with a female (AFAB) family member or friend, they would eventually have their periods at the same time.

Teens on the luna app also use the term "bluetoothing" periods a lot, particularly in the case where they have not yet started and so think their first period will be bluetoothed to them if they spend a lot of time with a mother, sister, or close friend who has periods.

Is period syncing real?

Despite this early research, there hasn’t been much scientific follow-up to confirm the theory. Current evidence is minimal, and scientists largely consider period syncing a myth.

While the idea can seem fun and relatable, it’s much more likely to be coincidence. Given that the average menstrual cycle lasts around 28 days, it’s inevitable that cycles will overlap at some point.

Supporting your teen’s understanding

Your teen might find comfort in the idea of sharing their period experience with others, and that’s perfectly natural.

However, it’s a good idea to remind them that every body is different, and their cycle follows its own unique rhythm. This can also be reassuring to them, if they find that their body doesn't perfectly match up to a friend or family member's.

As best you can, encourage them not to use anyone else’s cycle as a guide for predicting their own. Instead, consider introducing them to tools like period trackers that help them identify their individual patterns – luna has a great, straightforward tracking feature which is tailored to teenagers.