We know you’ve been curious about this one for a long time, and we can now answer it: Human sperm can survive in space.
A study has found that human sperm are able to survive and retain their viability in a zero-gravity environment. This is great news for those who favor space colonization as a solution to the existential threat posed by climate change and the decimation of Earth’s resources.
Or for people who just want to know in case they have sex at a hotel in space.
The study, conducted by Dexeus Women’s Health in Barcelona, was reported at the annual meeting of the European Society of Human Reproduction and Embryology in 2019. Researchers said sperm samples were not sent to space, but rather placed on a parabolic plane flight where they were exposed to microgravity.
The study’s investigators worked with a group of microgravity engineers from the Polytechnic University of Barcelona. The flights were conducted by the Aeroclub Barcelona-Sabadell.
According to a press release, researchers ran the full range of tests typically conducted for fertility testing. This includes measurements of concentration, motility, vitality, morphology and DNA fragmentation. The results showed no difference between the samples placed on the flight and the control group samples on Earth.
At the ESHRE conference, researchers explained this opens the possibility “of safely transporting male gametes to space and considering the possibility of creating a human sperm bank outside Earth.’
However, it’s important to note that the study used frozen sperm samples, not fresh ones.
“Some studies suggest a significant decrease in the motility of human fresh sperm samples,” Dexeus study’s lead investigator, Dr. Montserrat Boada said. “But nothing has been reported on the possible effects of gravitational differences on frozen human gametes, in which state they would be transported from Earth to space.”
Boada said using frozen samples was simply the first step in what will become a more comprehensive investigation. Her group plans to conduct further studies using larger sperm samples, longer periods of microgravity and fresh sperm.
“If the number of space missions increases in the coming years, and are of longer duration, it’s important to study the effects of long-term human exposure to space in order to face them,” Boada said. “It’s not unreasonable to start thinking about the possibility of reproduction beyond the Earth.’