A group of Japanese scientists has utilized sperm from mice who spent time on the International Space Station (ISS) to impregnate female mice on the ground. While previous studies have shown that freeze-dried mouse sperm preserved in space can be damaged by radiation, new findings suggest that sperm from live mice may not be affected in the same way.
On the International Space Station, radiation is around 100 times greater than on Earth. Not only did the kids show no harmful consequences from one parent spending time in the radiation environment, but the male reproductive organs appeared to be unaffected as well.
While freeze-dried mouse sperm was preserved in orbit for 9 months and was harmed by radiation in a previous study, the live mice in this study only spent 35 days on the ISS. In this investigation, 12 male mice were used, with some of them being placed in microgravity for the duration and others being kept in artificial gravity.
Researchers used the mouse sperm to artificially inseminate female mice who had never gone to space when they returned to Earth. The offspring were all in good health. The male mice were meticulously inspected, down to the molecular level, to see if they had suffered any damage while in space.
When the mice were returned to Earth, the scientists studied the testes, epididymides, and accessory glands. The accessory gland weight was reduced in both the artificial gravity (AG) and microgravity (MG) mice, but there was no change in gene expression. In preparation for a higher number of people spending time in space, scientists have been examining the impact of space on reproduction.
Birds, sea urchins, fish, newts, frogs, rats, and mice have all been studied so far. Male and female rats traveled into space together and failed to procreate or even mate, according to the results of those research.
While human reproduction hasn’t been thoroughly researched, there is some evidence.
After returning from space, male astronauts have been able to impregnate their wives practically immediately. A 2005 study found that female astronauts gave birth to 17 infants after returning from space, even though many female astronauts are nearing the end of their biological limits for generating progeny by the time they become astronauts.
