Imagine this: You're an astronaut hurtling through the cosmos on a multi-year journey to Mars, where even the simplest human functions—like eating, sleeping, or managing bodily needs—demand cutting-edge, scientifically vetted innovations. But what about menstruation? For women in space, this natural process isn't just a personal matter; it's a logistical challenge that could redefine autonomy and well-being on long missions. Yet, groundbreaking research is changing the game—and sparking heated debates along the way.
In the harsh environment of space, everyday activities require inventive fixes. Picture squeezing nutrition from sealed pouches, dozing in a sleeping bag tethered to the wall, or using a toilet powered by vacuum technology. These are the realities astronauts face, and menstruation is no exception. Female crew members must prepare meticulously for this biological inevitability, especially as missions stretch to the distant reaches of the moon or Mars, where survival demands systems humans weren't naturally built for.
As astrobiologist Lígia Coelho, a 51 Pegasi b Postdoctoral Fellow in astronomy at the College of Arts and Sciences and a fellow at the Carl Sagan Institute, puts it: "We're crafting all sorts of technologies to keep people alive in environments our bodies aren't designed for. The further we venture—to the moon and beyond—that challenge intensifies exponentially." Coelho, who applies her biology expertise to unravel life processes in space, is at the forefront of this effort.
But here's where it gets controversial: Why has something as fundamental as menstrual health been overlooked in space exploration? To address this, Coelho leads a project with AstroCup, a volunteer group of experts in science and space who recently put two menstrual cups through their paces on an uncrewed rocket flight. These cups, designed for collecting menstrual flow inside the body (like a flexible silicone cup that forms a seal, offering a reusable alternative to pads or tampons), were part of a payload in a specially engineered container. This container, crafted by aerospace engineers, monitored temperature, acceleration, and humidity to simulate space conditions. The team's findings were detailed in a paper titled "One Giant Leap for Womankind: First Menstrual Cup Tested in Spaceflight Conditions," published on December 2 in npj Women's Health.
Co-authors included Catarina Miranda, Miguel Morgado, and Diogo Nunes from the University of Lisbon, João Canas from aerospace company SpinWorks, as well as contributing authors André F. Henriques from the University of Lisbon and Adam B. Langeveld, a visiting scholar in astronomy at the College of Arts and Sciences and the Carl Sagan Institute.
The results were impressive. Through rigorous pre- and post-flight tests, the team confirmed that the silicon menstrual cups, produced by Finland-based company Lunette, maintained their shape and effectiveness after a 9.3-minute flight involving intense forces, particularly during launch and just before the parachute opened for descent. In fact, the cups endured accelerations even greater than those on a typical crewed mission, guaranteeing they'd hold up with astronauts aboard. A post-flight water test verified their structural soundness, while a simulation using glycerol (a substance mimicking blood's viscosity) proved they retained full functionality.
And this is the part most people miss: The methodology itself sets a gold standard. Coelho explained, "When you pioneer something on a rocket payload for the first time, your paper becomes a blueprint for others to follow. We invested immense effort into creating a foolproof process that anyone can replicate, complete with robust controls." This ensures future studies build on a solid foundation.
With these outcomes, Coelho and her collaborators demonstrate that an everyday silicon menstrual cup from Earth can reliably perform in space. But it's more than that—it's igniting a broader conversation in the space industry. "I'm deeply passionate about why menstrual devices aren't standard in space yet," Coelho shared. "We urgently need to discuss what true health autonomy means in this context." For beginners wondering about menstrual cups, think of them as eco-friendly, reusable tools that reduce waste and offer discreet protection, similar to how a contact lens case might hold a solution.
Currently, many female astronauts on missions up to six months opt for hormonal treatments to suppress menstruation. Pads or tampons are sometimes packed, but on extended trips to the moon or Mars—lasting years—these disposable items become impractical due to limited space and resources. Hormonal suppression poses its own risks over long periods, as it might require stockpiling medications for years, and NASA is investigating potential links to blood clots. In such scenarios, viable menstrual options aren't merely convenient; they're vital for sustaining health, productivity, and morale.
Without these choices, women on missions spanning five, ten, or more years could face prolonged interruptions to their reproductive health. Adopting a preferred menstrual method might even boost focus and contentment during the isolation of deep space travel. Coelho notes that cleaning and reusability need further exploration, but solutions like portable sterilization kits—commonly used on Earth for camping or hiking—could be adapted. Plus, menstrual underwear (absorbent undergarments) presents another straightforward alternative, akin to the single-use underwear worn by all astronauts on the International Space Station.
Here's the spark for debate: Is prioritizing menstrual autonomy in space a step toward true gender equality in exploration, or just an unnecessary luxury in an already resource-strapped environment? Some might argue it empowers women, while others could counter that it complicates logistics without adding core value. In February, the AstroCup team sent menstrual cups with participants on a simulated mission, the Hypatia II at Utah's Mars Desert Research Station, gathering insights on practicality and user feedback.
Looking ahead, they're planning additional rocket payloads, aiming to deploy various menstrual devices on the International Space Station. "It's proven—it works," Coelho affirmed. "Now, we can implement it and reshape health independence in space."
This story was written by Kate Blackwood for the College of Arts and Sciences.
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What are your thoughts? Do you believe space agencies should make menstrual health a priority for crew autonomy, or is it secondary to survival essentials? How might this affect perceptions of women in space? Agree or disagree—share your views in the comments below!
