Reading time: 2 minutes – Spotted on ScienceAlert
If the reproductive sciences have almost no secrets on Earth, space – and more particularly the change in gravity – poses a problem for scientists. Despite its ambitions to conquer space, humanity could come up against a major obstacle: the disorientation of spermatozoa.
An article from ScienceAlert tells us that a team led by researchers from the Polytechnic University of Catalonia (Spain) and the Dexeus University Hospital of Barcelona (Spain) collected fifteen sperm samples. She then divided the whole thing into two parts: one half remained on Earth, while the other half took off to be subjected to microgravity conditions, during parabolic flights.
The spermatozoa, taken for a stroll at 8,500 meters high, underwent variations in gravity and suggested quite negative changes. Microgravity did not kill them, but it led to a reduction in their motility (the ability of organisms to move) and their vitality (number of sperm remaining active). Concluding the experiment, the researchers write: “These negative consequences would be even greater if the exposure to the absence of gravity was longer.”
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The speed of sperm to reach their goal (the egg) was particularly affected. This result alerts to the fertilization of an egg in space, which will be significantly more difficult than on Earth. Fortunately, not all results are negative: sperm shape, oxidative stress (cause and/or consequence of chronic diseases) and apoptosis (programmed cell death) did not seem to be influenced by this change in gravity.
The research is only just beginning, but it automatically raises questions about reproduction in space. Not only regarding traditional reproduction, but also about assisted reproduction techniques, such as in vitro fertilization (IVF), which could be necessary if we are to settle on the Moon or Mars. Another mystery to solve: knowing why microgravity has such effects on sperm. Researchers are looking for a change in the chemical processes necessary to keep sperm healthy.
If sending human colonies into space are seriously considered (we see you Elon Musk), the reproduction of the species will be a relatively important detail. Until now, sexuality in space has not been a priority for astronauts and scientists. But since it is uncertain about our biological survival, the team behind this work wants other experiments to be carried out with human sperm. The researchers say: “With plans for extended space missions and growing interest in space tourism, the question of the likelihood of human conception in microgravity conditions has become even more relevant.”
Source: www.slate.fr
