(Photo of Sally Ride by NASA)
In the early days of spaceflight, doctors suspected that in microgravity, menstrual blood wouldn't flow out of the vagina, but remain inside and lead to infections.
But the experiences of more than 50 women who have been to space prove that assumption completely untrue. The New York Times quotes astronaut Dr. Rhea Seddon:
In a NASA oral history, Dr. Rhea Seddon, an astronaut who flew on three space shuttle missions in the 1980s and 1990s, said, “I’m not totally sure who had the first period in space, but they came back and said, ‘Period in space, just like period on the ground. Don’t worry about it.’”
There are, however, logistical difficulties with cleanliness, the management of menstrual blood, and the physical task of changing tampons in microgravity:
“The waste disposal systems onboard the U.S. side of the International Space Station that reclaim water from urine were not designed to handle menstrual blood, thus idealizing the minimization of breakthrough bleeding during menstrual suppression,” write the authors, whose review included discussions with the astronauts Dr. Ellen Baker and Serena Aunon, among others. Also, “the practicalities of personal hygiene while menstruating during spaceflight could be challenging, e.g., limited wash water supply or the task of changing hygiene products in microgravity.”
-via Glenn Reynolds