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Name: Unknown
Status:   student
Age:   20s
Location: N/A
Country: N/A
Date: 2000-2001

I know that it is common for a group of women that spend a lot of time together to eventually have their periods the same time of the month. Could you give me a scientific explanation as to why this is the case? It has happened with my wife, sister, and mother-in law in the same house, and also with a bunch of different women at work who all sit next to each other. Does it have something to do with pheromones?

To my knowledege no one yet knows...pheromones?


This topic has surfaced a number of times with much speculation. Pheromones do regulate reproduction in insects species and it has been hypothesized that it may play a role in all mammals as well.

Steve Sample

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