Menstruation in space will be studied for the first time:Researchers set out to solve one of spaceflight’s most overlooked questions with ‘Operation Period’

For more than six decades, humans have been traveling to space. Astronauts have walked on the Moon, lived aboard space stations for months, and conducted thousands of scientific experiments in microgravity. Yet despite all these achievements, one basic aspect of human health remains surprisingly understudied: menstruation. In fact, although more than 100 women and gender-diverse people have traveled beyond Earth, no mission has ever been dedicated to studying how periods behave in space. That is now set to change.
Groundbreaking mission by ‘Operation Period’ A nonprofit organization called Operation Period is preparing a historic mission that will become the first dedicated scientific study of menstruation in microgravity. Scheduled for 2027, the mission, named Operation Period-01 (OP-01), will fly aboard a Virgin Galactic suborbital spaceflight and aims to answer long-standing questions about how menstruation functions in a weightless environment. The project is being carried out in partnership with Virgin Galactic, which says the mission highlights the growing role of commercial spaceflights in advancing research on important but often overlooked aspects of human health.
A question space agencies never fully answered The lack of research on menstruation in space is not because women have not traveled to orbit. Women have been part of human spaceflight programs for decades. However, surprisingly little scientific data exists on how the menstrual cycle functions in a microgravity environment. One famous example often cited by researchers involves NASA astronaut Sally Ride, the first American woman in space. Before her six-day mission in 1983, engineers reportedly asked whether 100 tampons would be enough for the trip. While the story is often remembered as a humorous example of early misunderstandings about women’s health, it also highlights a deeper issue: space agencies simply did not have enough information.
Even today, researchers say many important questions remain unanswered. How does menstrual fluid move in weightlessness? Do menstrual products work the same way in space as they do on Earth? Could prolonged exposure to microgravity affect menstrual health during long-duration missions? Scientists still do not have clear answers. The mission that wants to change that Operation Period was founded by Manju Bangalore and Priya Abiram to improve menstrual health awareness and access to period products. While working in this field, they realized that menstruation remains largely unstudied in space.
To address this gap, they launched Operation Period-01, a mission that will study how periods and menstrual products behave in microgravity.
The researchers themselves will travel on a Virgin Galactic suborbital flight in 2027 and conduct the experiments during the mission.

Why is this research important? Understanding menstruation in space is important as future astronauts may spend months on the Moon or even years on missions to Mars. Currently, many astronauts suppress their periods using hormonal treatments, partly because there is little scientific data on how menstruation works in microgravity.
Researchers say better data will help astronauts make informed choices and allow mission planners to prepare the right medical supplies and healthcare support for long-duration space missions. Also read: Think before you tap ‘Allow’ to continue: Microphone permissions can put your privacy at risk if granted; here’s when to say yes and no

How microgravity changes the human body The human body behaves differently in space. Astronauts experience muscle loss, bone density reduction, fluid shifts toward the head, changes in vision, and alterations to the immune system. Even simple everyday activities become more complicated in a weightless environment. Fluids, in particular, behave very differently in microgravity. On Earth, gravity influences how liquids move. In space, fluids can form floating droplets, cling to surfaces, or travel in unexpected ways. Researchers believe these differences may also affect menstrual fluid dynamics, but because no dedicated study has been conducted, nobody knows exactly how significant those effects might be. A historic moment for space medicine When Operation Period-01 launches in 2027, it will become the first mission dedicated to studying menstruation in space. As agencies prepare for longer stays on the Moon and future missions to Mars, understanding every aspect of human health is becoming increasingly important. Researchers hope the mission will help fill a major gap in space medicine by providing valuable data on menstrual health in microgravity.